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1. A study of spin alignment of $\rho(770)^{\pm}$ and $\omega(782)$ mesons in hadronic Z $^0$ decays

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., De Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: Physics, Density matrix, Particle physics, Range (particle radiation), Physics and Astronomy (miscellaneous), Meson, 010308 nuclear & particles physics, Hadron, 01 natural sciences, Omega, Helicity, 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Engineering (miscellaneous), Particle Physics - Experiment, Spin-½
Abstract: The helicity density matrix elements rho[00] of rho(770)+- and omega(782) mesons produced in Z decays have been measured using the OPAL detector at LEP. Over the measured meson energy range, the values are compatible with 1/3, corresponding to a statistical mix of helicity -1, 0 and +1 states. For the highest accessible scaled energy range 0.3 < x_E < 0.6, the measured rho[00] values of the rho(770)+- and the omega are 0.373 +- 0.052 and 0.142 +- 0.114, respectively. These results are compared to measurements of other vector mesons. The helicity density matrix elements rho[00] of rho(770)+- and omega(782) mesons produced in Z decays have been measured using the OPAL detector at LEP. Over the measured meson energy range, the values are compatible with 1/3, corresponding to a statistical mix of helicity -1, 0 and +1 states. For the highest accessible scaled energy range 0.3 < x_E < 0.6, the measured rho[00] values of the rho(770)+- and the omega are 0.373 +- 0.052 and 0.142 +- 0.114, respectively. These results are compared to measurements of other vector mesons. The helicity density matrix elements rho[00] of rho(770)+- and omega(782) mesons produced in Z decays have been measured using the OPAL detector at LEP. Over the measured meson energy range, the values are compatible with 1/3, corresponding to a statistical mix of helicity -1, 0 and +1 states. For the highest accessible scaled energy range 0.3 < x_E < 0.6, the measured rho[00] values of the rho(770)+- and the omega are 0.373 +- 0.052 and 0.142 +- 0.114, respectively. These results are compared to measurements of other vector mesons. The helicity density matrix elements rho[00] of rho(770)+- and omega(782) mesons produced in Z decays have been measured using the OPAL detector at LEP. Over the measured meson energy range, the values are compatible with 1/3, corresponding to a statistical mix of helicity -1, 0 and +1 states. For the highest accessible scaled energy range 0.3 < x_E < 0.6, the measured rho[00] values of the rho(770)+- and the omega are 0.373 +- 0.052 and 0.142 +- 0.114, respectively. These results are compared to measurements of other vector mesons. The helicity density matrix elements rho[00] of rho(770)+- and omega(782) mesons produced in Z decays have been measured using the OPAL detector at LEP. Over the measured meson energy range, the values are compatible with 1/3, corresponding to a statistical mix of helicity -1, 0 and +1 states. For the highest accessible scaled energy range 0.3 < x_E < 0.6, the measured rho[00] values of the rho(770)+- and the omega are 0.373 +- 0.052 and 0.142 +- 0.114, respectively. These results are compared to measurements of other vector mesons.
Published: 2000
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2. Measurement of |Vcb| using decays

Author: G. Abbiendi, K. Ackerstaff, P.F. Akesson, G. Alexander, J. Allison, K.J. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, I. Bailey, A.H. Ball, E. Barberio, R.J. Barlow, J.R. Batley, S. Baumann, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, O. Biebel, A. Biguzzi, I.J. Bloodworth, P. Bock, J. Böhme, O. Boeriu, D. Bonacorsi, M. Boutemeur, S. Braibant, P. Bright-Thomas, L. Brigliadori, R.M. Brown, H.J. Burckhart, J. Cammin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, C. Ciocca, P.E.L. Clarke, E. Clay, I. Cohen, O.C. Cooke, J. Couchman, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, G.M. Dallavalle, S. Dallison, R. Davis, A. de Roeck, P. Dervan, K. Desch, B. Dienes, M.S. Dixit, M. Donkers, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, P.G. Estabrooks, E. Etzion, F. Fabbri, A. Fanfani, M. Fanti, A.A. Faust, L. Feld, P. Ferrari, F. Fiedler, M. Fierro, I. Fleck, A. Frey, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, D.M. Gingrich, D. Glenzinski, J. Goldberg, W. Gorn, C. Grandi, K. Graham, E. Gross, J. Grunhaus, M. Gruwé, P.O. Günther, C. Hajdu, G.G. Hanson, M. Hansroul, M. Hapke, K. Harder, A. Harel, C.K. Hargrove, M. Harin-Dirac, A. Hauke, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, C. Hensel, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, P.R. Hobson, A. Hocker, K. Hoffman, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, D.C. Imrie, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, M. Jimack, C.R. Jones, P. Jovanovic, T.R. Junk, N. Kanaya, J. Kanzaki, G. Karapetian, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, D.H. Kim, K. Klein, A. Klier, T. Kobayashi, M. Kobel, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, T. Kuhl, M. Kupper, P. Kyberd, G.D. Lafferty, H. Landsman, D. Lanske, I. Lawson, J.G. Layter, A. Leins, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, J. Lillich, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Lu, J. Ludwig, A. Macchiolo, A. Macpherson, W. Mader, M. Mannelli, S. Marcellini, T.E. Marchant, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, T.J. McMahon, R.A. McPherson, F. Meijers, P. Mendez-Lorenzo, F.S. Merritt, H. Mes, I. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, A. Okpara, M.J. Oreglia, S. Orito, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, B. Poli, J. Polok, M. Przybycień, A. Quadt, C. Rembser, H. Rick, S.A. Robins, N. Rodning, J.M. Roney, S. Rosati, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, P. Scharff-Hansen, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, S. Spagnolo, M. Sproston, A. Stahl, K. Stephens, K. Stoll, D. Strom, R. Ströhmer, B. Surrow, S.D. Talbot, S. Tarem, R.J. Taylor, R. Teuscher, M. Thiergen, J. Thomas, M.A. Thomson, E. Torrence, S. Towers, T. Trefzger, I. Trigger, Z. Trócsányi, E. Tsur, M.F. Turner-Watson, I. Ueda, R. Van Kooten, P. Vannerem, M. Verzocchi, H. Voss, D. Waller, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, T. Wengler, N. Wermes, D. Wetterling, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, V. Zacek, and D. Zer-Zion
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, Branching fraction, Form factor (quantum field theory), Zero (complex analysis), Value (computer science), 01 natural sciences, Recoil, 0103 physical sciences, Heavy quark effective theory, Matrix element, 010306 general physics
Abstract: The magnitude of the Cabibbo-Kobayashi-Maskawa matrix element Vcb has been measured using B0 to D*l nu decays recorded on the Z0 peak using the OPAL detector at LEP. The D* to D0 pi+ decays were reconstructed both in the particular decay modes D0 to K- pi+ and D0 to K- pi+ pi- and via an inclusive technique. The product of |Vcb| and the decay form factor of the B0 to D* l nu transition at zero recoil F(1) was measured to be F(1)|Vcb| = (37.1+-1.0+-2.0)x10^-3, where the uncertainties are statistical and systematic respectively. By using Heavy Quark Effective Theory calculations for F(1), a value of |Vcb| = (40.7+-1.1+-2.2+-1.6)x 10^-3 was obtained, where the third error is due to theoretical uncertainties in the value of F(1). The branching ratio Br(B0 to D* l nu) was also measured to be (5.26+-0.20+-0.46)%.
Published: 2000
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3. Search for anomalous production of acoplanar di-lepton events in ${\rm e^+e^-}$ collisions at $\sqrt{s} =$ 183 and 189 GeV

Author: P. Ferrari, Randall Sobie, H. Mes, Naoko Kanaya, R. J. Hemingway, G. D. Lafferty, I. P. Duerdoth, S. Braibant, J. Lillich, Christopher Hawkes, German Martinez, K. Stephens, H. O. Ogren, B. W. Kennedy, P. Jovanovic, C. Littlewood, Christoph Geich-Gimbel, Gideon Bella, K. Stoll, Andris Skuja, S. Petzold, Austin Ball, Guenter Duckeck, A. A. Faust, P. Hüntemeyer, Daniel Lellouch, L. Brigliadori, H. J. Burckhart, Jacqueline Batley, Peter R Hobson, D. Zer-Zion, Takehiko Mori, Peter Krieger, Vakhtang Kartvelishvili, Tetsuro Mashimo, S. W. O'Neale, M. F. Turner-Watson, K. J. Anderson, Sachio Komamiya, A. Okpara, P. Mättig, T. J. McMahon, Richard Teuscher, R. Kowalewski, Erez Etzion, M. A. Thomson, A. T. Watson, Matthias Schröder, D. E. Plane, F. Fiedler, M. Thiergen, J. E. Conboy, A. Fürtjes, S. Arcelli, Alessandro Montanari, I. Meyer, C. Couyoumtzelis, T. P. Kokott, J. Dubbert, D. Waller, E. K. U. Gross, M. Verzocchi, W. Gorn, R. K. Carnegie, Shlomit Tarem, Lutz Feld, R. Van Kooten, T. Saeki, G. M. Dallavalle, Alessandra Fanfani, R. Davis, G. Gaycken, P. G. Bright-Thomas, J. A. Wilson, M. Sproston, C. R. Jones, J. Böhme, B. Surrow, M. Schumacher, M. Boutemeur, F. S. Merritt, Gideon Alexander, Thomas E Marchant, Paolo Capiluppi, Michael Hildreth, Achim Stahl, I. Trigger, Stefan Schmitt, Alain Bellerive, M. Kolrep, N. L. Rodning, T. Kuhl, Paul Kyberd, F. K. Loebinger, P. Dervan, S. Yamashita, P. Scharff-Hansen, B. Poli, F. Odorici, K. Graham, F. Wäckerle, D. R. Ward, Tara Shears, H. Voss, R. J. Barlow, Georges Azuelos, Ivor Fleck, Richard Nisius, B. List, Ekg Sarkisyan, D. M. Gingrich, P. Igo-Kemenes, E. Tsur, Ehud Duchovni, D. Axen, A. Jawahery, Oana Elena Vickey Boeriu, J. Grunhaus, J. Bechtluft, J. A. McKenna, D. J. Miller, Joleen Pater, K. W. Bell, J. Goldberg, Dave Charlton, Marco Cuffiani, K. Ishii, H. Jeremie, S. B. Anderson, Shoji Asai, M. Jimack, A. M. Smith, K. Hoffman, A. Klier, A. Michelini, Juergen Thomas, M. Przybycień, H. A. Neal, M. Fanti, T. Kress, J. C. Hill, J. M. Roney, S. Spagnolo, A. M. Rossi, W. R. Gibson, W. J. McDonald, B. C. Shen, A. A. Carter, I. J. Bloodworth, M. Donkers, Kiyotomo Kawagoe, K. Harder, Siegfried Bethke, D. Liu, A. K. Honma, Robert McPherson, Paolo Giacomelli, T. Kobayashi, Stan Bentvelsen, O. Schaile, M. Hansroul, Koichi Nagai, John Allison, W. G. Scott, J. Schieck, R. Hawkings, I. Nakamura, H. Landsman, Peter Sherwood, I. Cohen, R. D. Heuer, Christoph Rembser, James Pinfold, S. Robertson, Yoram Rozen, W. Mohr, Fabrizio Fabbri, A. Frey, R. Perez-Ochoa, R. Seuster, Giovanni Abbiendi, A. J. Martin, Claudia Ciocca, M. Harin-Dirac, S. A. Robins, R. L. Coxe, T. Trefzger, R. J. Homer, R. G. Kellogg, Junichi Kanzaki, J. Polok, R. M. Brown, D. Karlen, D. R. Rust, P. Mendez-Lorenzo, F. G. Oakham, R. Liebisch, K. Ackerstaff, Alexander Wagner, A. Macchiolo, J. Ludwig, A. Hocker, Daniele Bonacorsi, K. Runge, P. Bock, Lorne Levinson, Csaba Hajdu, D. Glenzinski, Dezso Horvath, M. J. Losty, Stefano Marcellini, E. L. Barberio, D. Chrisman, G. D. Long, V. Zacek, K. R. Hossain, W. M. Sang, J. Couchman, W. Mader, O. C. Cooke, P. Pfeifenschneider, J. W. Gary, Marcello Mannelli, C. K. Hargrove, Stephen Lloyd, J. Patt, D. C. Imrie, André Schöning, C. H. Shepherd-Themistocleous, J. von Krogh, O. Sahr, C. Sbarra, F. R. Jacob, G. P. Siroli, M. Gruwé, D. Wetterling, Christoph Schwick, K. Roscoe, P. Gagnon, S. Baumann, E. Torrence, Zoltan Laszlo Trocsanyi, E. Clay, Dong Hee Kim, J. Lauber, E. A. Mckigney, S. D. Talbot, T. Behnke, Satoshi Mihara, T. R. Junk, D. Lanske, D. I. Futyan, P. S. Wells, Terry Richard Wyatt, O. Runolfsson, P. G. Estabrooks, R. K. Keeler, N. K. Watson, Arnulf Quadt, P. M. Watkins, Claudio Grandi, J. S. White, M. Fierro, S. Rosati, A. Harel, Ikuo Ueda, D. M. Strom, A. D. Schaile, Gabriella Pasztor, J. Lu, P. Vannerem, G. A. Snow, C. P. Ward, Raimund Ströhmer, S. Söldner-Rembold, P. Poffenberger, Beatrix Dienes, J. Letts, C. Y. Chang, P. Taras, A. Macpherson, K. Sachs, Shlomo Dado, Giora Mikenberg, Klaus Desch, S. F. Ashby, R. Howard, Otmar Biebel, P. I. Kayal, Norbert Wermes, Sherry Towers, T. Kawamoto, S. Orito, S. Betts, M. Hapke, M. J. Oreglia, Gregor Herten, J. E. Pilcher, A. W. Lloyd, G. W. Wilson, M. Hauschild, S.J. Dallison, J. R. Carter, G. N. Patrick, A. Biguzzi, J. G. Layter, P. E.L. Clarke, J. P. Martin, S. De Jong, H. Rick, G. G. Hanson, G. Giacomelli, I. Lawson, A. De Roeck, M. Kobel, M. S. Dixit, and Frans Meijers
Subjects: Physics, Particle physics, Physics and Astronomy (miscellaneous), Branching fraction, Electron–positron annihilation, High Energy Physics::Phenomenology, Standard Model, Nuclear physics, Chargino, Neutralino, Higgs boson, High Energy Physics::Experiment, Nuclear Experiment, Engineering (miscellaneous), Minimal Supersymmetric Standard Model, Lepton
Abstract: A selection of di-lepton events with significant missing transverse momentum has been performed using a total data sample of 237.4 pb-1 at e+e- centre-of-rnass energies of approximately 183 GeV and 189 GeV. The observed numbers of events - 78 at 183 GeV and 301 at 189 GeV - are consistent with the numbers expected from Standard Model processes, which arise predominantly from W+W- production with both W bosons decaying leptonically. This topology is also an experimental signature for the pair production of new particles that decay to a charged lepton accompanied by one or more invisible particles. Discrimination techniques are described that optimise the sensitivity to particular new physics channels. No evidence for new phenomena is apparent. Upper limits on the production cross-section times branching ratio squared for sleptons and for leptonically decaying charginos and charged Higgs are presented in a manner intended to minimise the number of model assumptions. Assuming a 100% branching ratio for the decay l±R → l±χ01, where χ01 is the lightest neutralino, we exclude at 95% CL: right-handed smuons with masses below 82.3 GeV for mμ- - mχ01 > 3 GeV and right-handed staus with masses below 81.0 GeV for mτ- -mχ01 > 8 GeV. Right-handed selectrons are excluded at 95% CL for masses below 87.1 GeV for mẽ - mχ01 > 5 GeV, within the framework of the Minimal Supersymmetric Standard Model assuming μ, < - 100 GeV and tan β= 1.5. Charged Higgs bosons, H±, are excluded at 95% CL for masses below 82.8 GeV, assuming a 100% branching ratio for the decay H± → τ ± vτ.
Published: 2000
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4. A study of parton fragmentation in hadronic Z $^0$ decays using $\Lambda\bar\Lambda$ correlations

Author: B. Nellen, H. G. Evans, I. Cohen, Tara Shears, Christoph Rembser, C. Hartmann, D. E. Plane, T. J. McMahon, C. Couyoumtzelis, Stephen Hillier, G. Gaycken, P. G. Bright-Thomas, J. Dubbert, G. M. Dallavalle, S. A. Robins, R. K. Carnegie, M. Schumacher, M. Herndon, M. Bobinski, R. Liebisch, K. Stoll, P. G. Estabrooks, R. K. Keeler, J. A. Wilson, J. Böhme, Andris Skuja, K. Ackerstaff, Matthias Schröder, M. Thiergen, Gregor Herten, N. K. Watson, Dave Charlton, S. Petzold, P. M. Watkins, D. Lazic, A. Macpherson, M. Fierro, Randall Sobie, G. D. Lafferty, A. J. Martin, F. Odorici, Tetsuro Mashimo, S. R. Lautenschlager, J. Grunhaus, W. Mader, Erez Etzion, C. K. Hargrove, S. Betts, M. Hapke, S. Yamashita, J. E. Pilcher, Stefan Kluth, Shlomit Tarem, Stefan Schmitt, K. Roscoe, H. A. Neal, R. Bürgin, B. Surrow, C. Y. Chang, D. R. Rust, A. W. Lloyd, P. Igo-Kemenes, Georges Azuelos, P. E.L. Clarke, O. Runolfsson, A. D. Schaile, Gabriella Pasztor, E. Tsur, P. Vannerem, M. J. Oreglia, Klaus Kurt Desch, G. W. Wilson, W. Gorn, K. Ishii, H. Jeremie, M. Hauschild, C. Markopoulos, John Allison, J. Lauber, G. Yekutieli, S. Baumann, M. Przybycień, Guenter Duckeck, Sachio Komamiya, A. T. Watson, A. A. Carter, R. Howard, M. Verzocchi, K. W. Bell, P. Taras, Ron Folman, A. M. Lee, E. von Törne, E. A. Mckigney, E. Torrence, Claudio Grandi, J. S. White, J. Pálinkás, T. P. Kokott, G. A. Snow, C. P. Ward, J. P. Martin, J. R. Carter, S. Söldner-Rembold, G. N. Patrick, R. Mir, R. Hawkings, Otmar Biebel, E. Clay, Shoji Asai, Gideon Bella, Ekg Sarkisyan, T. Saeki, R. Davis, J. C. Hill, J. Letts, M. Fanti, O. Schaile, H. J. Burckhart, Daniel Lellouch, D. I. Futyan, Jacqueline Batley, P. I. Kayal, Takehiko Mori, H. Mes, James Pinfold, R. Perez-Ochoa, R. Seuster, Giovanni Abbiendi, S. De Jong, Claire Shepherd-Themistocleous, S. Robertson, Daniele Bonacorsi, S. B. Anderson, K. Sachs, Shlomo Dado, I. P. Duerdoth, S. Braibant, Norbert Wermes, Sherry Towers, T. Kawamoto, W. J. McDonald, W. R. Gibson, B. C. Shen, Robert McPherson, M. Boutemeur, F. S. Merritt, D. M. Strom, P. Mättig, J. Gascon, S. Orito, K. Harder, F. G. Oakham, B. Schmitt, E. L. Barberio, R. E. Schmitz, R. D. Heuer, Fabrizio Fabbri, Sven Menke, D. Lanske, Siegfried Bethke, D. Liu, Giora Mikenberg, S. F. Ashby, H. Rick, V. Zacek, R. Van Kooten, Stan Bentvelsen, J. von Krogh, P. Hüntemeyer, Raimund Ströhmer, R. J. Hemingway, A. A. Faust, A. K. Honma, W. G. Scott, S. D. Talbot, J. W. Gary, C. R. Jones, D. S. Koetke, R. M. Brown, Lorne Levinson, M. F. Turner-Watson, M. Gruwé, L. A. del Pozo, Marcello Mannelli, Peter R Hobson, I. Nakamura, B. W. Kennedy, P. Jovanovic, D. M. Gingrich, P. Scharff-Hansen, J. Bechtluft, Richard Teuscher, I. J. Bloodworth, D. Zer-Zion, A. S. Turcot, F. Fiedler, P. Poffenberger, J. A. McKenna, T. R. Junk, D. Eatough, Austin Ball, Peter Krieger, A. Macchiolo, A. M. Smith, P. S. Wells, D. Glenzinski, Dezso Horvath, M. J. Losty, R. G. Kellogg, G. G. Hanson, Jean-Arcady Meyer, Terry Richard Wyatt, C. M. Hawkes, Yoram Rozen, M. Kolrep, T. Behnke, R. Bartoldus, Alessandro Montanari, T. Kuhl, H. O. Ogren, J. Polok, G. Giacomelli, I. Lawson, Richard Nisius, Christoph Geich-Gimbel, D. Karlen, A. De Roeck, M. Kobel, O. C. Cooke, Beatrix Dienes, B. List, Marco Cuffiani, P. Pfeifenschneider, M. S. Dixit, Frans Meijers, Vakhtang Kartvelishvili, J. E. Conboy, A. Fürtjes, P. Gagnon, Stefano Marcellini, L. Brigliadori, N. Altekamp, H. Voss, R. J. Barlow, A. Biguzzi, D. J. Miller, J. Patt, J. G. Layter, A. Sittler, Zoltan Laszlo Trocsanyi, André Schöning, O. Sahr, W. M. Sang, S. W. O'Neale, K. J. Anderson, S. D. Bird, D. Axen, A. Jawahery, Peter Sherwood, Alexander Wagner, J. Ludwig, K. Runge, P. Bock, Paolo Giacomelli, C. Sbarra, F. R. Jacob, M. Hansroul, Paul Kyberd, F. K. Loebinger, J. Steuerer, Ivor Fleck, C. Burgard, Joleen Pater, A. Klier, R. J. Homer, Satoshi Mihara, Kiyotomo Kawagoe, Achim Stahl, K. R. Hossain, D. C. Imrie, G. P. Siroli, K. Stephens, Christoph Schwick, C. Littlewood, V. Gibson, I. Trigger, F. Scharf, German Martinez, D. R. Ward, T. Kress, J. M. Roney, Ehud Duchovni, Koichi Nagai, J. Schieck, W. Mohr, M. Jimack, M. A. Thomson, A. Michelini, Claudia Ciocca, F. Wöckerle, E. K. U. Gross, M. Sproston, S. M. Gascon-Shotkin, Satoshi Tanaka, T. Kobayashi, A. M. Rossi, R. L. Coxe, A. Hocker, D. Chrisman, G. D. Long, Volker Blobel, Michael Hildreth, Alain Bellerive, Stephen Lloyd, N. L. Rodning, R. Kowalewski, S. Arcelli, Gideon Alexander, Paolo Capiluppi, and J. Goldberg
Subjects: Physics, Particle physics, Physics and Astronomy (miscellaneous), Electron–positron annihilation, Hadron, Hyperon, Parton, Lambda, Lambda baryon, Nuclear physics, Baryon, High Energy Physics::Experiment, Rapidity, Engineering (miscellaneous)
Abstract: The correlated production of $\Lambda$ and $\bar\Lambda$ baryons has been studied using 4.3 million multihadronic ${\rm Z}^0$ decays recorded with the Opal detector at Lep. Lambda pairs were investigated in the full data sample and for the first time also in 2-jet and 3-jet events selected with the $k_\perp$ algorithm. The distributions of rapidity differences from correlated $\Lambda\bar\Lambda$ pairs exhibit short-range, local correlations and prove to be a sensitive tool to test models, particularly for 2-jet events. The Jetset model describes the data best but some extra parameter tuning is needed to improve agreement with the experimental results in the rates and the rapidity spectra simultaneously. The recently developed modification of Jetset, the MOdified Popcorn Scenarium (Mops), and also Herwig do not give satisfactory results. This study of di-lambda production in 2- and 3-jet events supports the short-range compensation of quantum numbers.
Published: 2000
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5. A study of $\mathrm{B_s^0}$ meson oscillation using hadronic $\mathrm Z^0$ decays containing leptons

Author: H. O. Ogren, Erez Etzion, Christoph Geich-Gimbel, Shlomit Tarem, Sachio Komamiya, D. Axen, S. Yamashita, A. T. Watson, A. Jawahery, B. Surrow, Richard Teuscher, P. Igo-Kemenes, Vakhtang Kartvelishvili, F. Fiedler, A. Biguzzi, J. E. Conboy, A. Fürtjes, J. G. Layter, K. Ishii, H. Jeremie, Peter Sherwood, Daniele Bonacorsi, J. von Krogh, M. Gruwé, D. Wetterling, T. P. Kokott, T. Saeki, Lutz Feld, Kiyotomo Kawagoe, O. C. Cooke, Alexander Wagner, A. Macchiolo, W. R. Gibson, P. Pfeifenschneider, T. J. McMahon, C. Couyoumtzelis, S. Betts, A. Macpherson, J. Dubbert, J. Ludwig, M. Hapke, K. Harder, S. A. Robins, R. Liebisch, K. Ackerstaff, J. Letts, R. K. Carnegie, G. Gaycken, P. G. Bright-Thomas, J. A. Wilson, J. Böhme, Raimund Ströhmer, M. Kolrep, Alessandra Fanfani, R. Davis, S. Baumann, K. Runge, P. Bock, M. Przybycień, T. Kress, E. A. Mckigney, A. A. Carter, I. J. Bloodworth, J. Patt, André Schöning, O. Schaile, W. J. McDonald, Giovanni Abbiendi, M. Schumacher, Matthias Schröder, B. C. Shen, R. J. Hemingway, M. A. Thomson, J. Lauber, M. Boutemeur, F. S. Merritt, O. Sahr, Klaus Desch, P. E.L. Clarke, R. Howard, S. Robertson, P. Poffenberger, Siegfried Bethke, D. Liu, A. K. Honma, K. R. Hossain, C. H. Shepherd-Themistocleous, K. Sachs, Christopher Hawkes, W. M. Sang, S. B. Anderson, Shlomo Dado, J. Grunhaus, E. K. U. Gross, R. L. Coxe, M. Thiergen, F. Odorici, W. G. Scott, Yoram Rozen, J. P. Martin, B. W. Kennedy, T. Kuhl, S. De Jong, I. Nakamura, Richard Nisius, J. Goldberg, J. Bechtluft, M. Sproston, P. Jovanovic, M. J. Oreglia, Stan Bentvelsen, Austin Ball, K. Stoll, S. D. Talbot, R. M. Brown, Lorne Levinson, Andris Skuja, Peter Krieger, B. List, H. Rick, Marco Cuffiani, P. Mendez-Lorenzo, Junichi Kanzaki, J. Polok, D. I. Futyan, Gregor Herten, K. Hoffman, Giora Mikenberg, S. F. Ashby, D. Glenzinski, Paolo Giacomelli, D. Karlen, T. Behnke, R. D. Heuer, Alessandro Montanari, Daniel Lellouch, T. R. Junk, P. S. Wells, M. Hansroul, Beatrix Dienes, A. Hocker, J. A. McKenna, I. Cohen, S. Petzold, Juergen Thomas, Tetsuro Mashimo, M. F. Turner-Watson, A. D. Schaile, Randall Sobie, G. D. Lafferty, R. Hawkings, Christoph Rembser, Dezso Horvath, M. J. Losty, Takehiko Mori, A. Okpara, Terry Richard Wyatt, P. Mättig, G. D. Long, G. G. Hanson, C. Y. Chang, Gabriella Pasztor, P. Gagnon, H. Landsman, J. M. Roney, M. Verzocchi, J. E. Pilcher, H. Mes, P. G. Estabrooks, R. K. Keeler, N. K. Watson, M. Harin-Dirac, P. Vannerem, G. A. Snow, C. P. Ward, D. C. Imrie, R. J. Homer, G. Giacomelli, I. Lawson, A. De Roeck, M. Kobel, Arnulf Quadt, Naoko Kanaya, P. M. Watkins, Guenter Duckeck, A. Sittler, Zoltan Laszlo Trocsanyi, I. P. Duerdoth, S. Braibant, F. G. Oakham, P. Taras, Dong Hee Kim, Koichi Nagai, J. Schieck, C. Sbarra, F. R. Jacob, Stefan Schmitt, G. P. Siroli, S. Söldner-Rembold, W. Gorn, J. R. Carter, G. N. Patrick, E. L. Barberio, A. J. Martin, M. S. Dixit, Stephen Lloyd, Frans Meijers, Satoshi Mihara, P. Hüntemeyer, Christoph Schwick, K. Roscoe, W. Mohr, John Allison, Otmar Biebel, Georges Azuelos, E. Tsur, Shoji Asai, P. Scharff-Hansen, A. A. Faust, Achim Stahl, O. Runolfsson, K. W. Bell, N. Altekamp, H. Voss, A. W. Lloyd, E. Torrence, R. J. Barlow, D. J. Miller, J. Couchman, W. Mader, Ehud Duchovni, A. M. Smith, R. G. Kellogg, K. Stephens, J. C. Hill, E. Clay, C. K. Hargrove, K. Graham, G. W. Wilson, M. Jimack, Csaba Hajdu, S. Spagnolo, C. Littlewood, Tara Shears, P. I. Kayal, Claudio Grandi, J. S. White, Stefano Marcellini, M. Hauschild, German Martinez, Ekg Sarkisyan, James Pinfold, L. Brigliadori, R. Perez-Ochoa, R. Seuster, V. Gibson, A. Michelini, Norbert Wermes, Sherry Towers, D. E. Plane, T. Kawamoto, D. Lanske, V. Zacek, Paul Kyberd, F. K. Loebinger, I. Trigger, T. Kobayashi, J. W. Gary, J. Steuerer, Ivor Fleck, D. R. Ward, S. Orito, G. M. Dallavalle, Marcello Mannelli, Joleen Pater, A. Klier, H. A. Neal, M. Fierro, R. Kowalewski, S. W. O'Neale, S. Arcelli, K. J. Anderson, Gideon Alexander, Paolo Capiluppi, Gideon Bella, H. J. Burckhart, Jacqueline Batley, C. R. Jones, M. Fanti, Peter R Hobson, D. Zer-Zion, Robert McPherson, Fabrizio Fabbri, A. Frey, R. Van Kooten, Claudia Ciocca, F. Wäckerle, D. M. Gingrich, A. M. Rossi, Michael Hildreth, Alain Bellerive, N. L. Rodning, P. Dervan, B. Poli, D. R. Rust, S. Rosati, A. Harel, Ikuo Ueda, D. M. Strom, and J. Lu
Subjects: Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, Oscillation, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Charge (physics), Jet (particle physics), Nuclear physics, High Energy Physics::Experiment, Production (computer science), Engineering (miscellaneous), Lepton
Abstract: A sample of ${\rm Z}^0$ decays containing b-flavoured hadrons is tagged using leptons, and events having precise proper time measurements are selected. These events are used to study ${\rm B}^0_{\rm s}$ oscillations. The flavour (b or $\rm \bar{b}$) at decay is determined from the lepton charge while the flavour at production is determined from jet charge or the charge of a second lepton, where available. The experiment was not able to resolve the oscillatory behaviour, and we deduce that the ${\rm B}^0_{\rm s}$ oscillation frequency $\Delta m_{\rm s} > 5.2$ ps$^{-1}$ at the 95% confidence level.
Published: 1999
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6. Measurement of the W+W−γ cross-section and first direct limits on anomalous electroweak quartic gauge couplings

Author: Abbiendi, G., Ackerstaff, K., Akesson, P.F., Alexander, G., Allison, John, Anderson, K.J., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Bailey, I., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karapetian, G., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kupper, M., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lawson, I., Layter, J.G., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schieck, J., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wengler, T., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Photon, 010308 nuclear & particles physics, Physics beyond the Standard Model, Electroweak interaction, FOS: Physical sciences, Photon energy, Lambda, 01 natural sciences, Measure (mathematics), High Energy Physics - Experiment, Standard Model, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, 010306 general physics, Particle Physics - Experiment, Energy (signal processing)
Abstract: A study of W+W- events accompanied by hard photon radiation produced in e+e- collisions at LEP is presented. Events consistent with two on-shell W-bosons and an isolated photon are selected from 183pb^-1 of data recorded at root{s}=189GeV. From these data, 17 W+W-gamma candidates are selected with photon energy greater than 10GeV, consistent with the Standard Model expectation. These events are used to measure the e+e- to W+W-gamma cross-section within a set of geometric and kinematic cuts; sigma{W+W-gamma} = 136+-37+-8 fb, where the first error is statistical and the second systematic. The photon energy spectrum is used to set the first direct, albeit weak, limits on possible anomalous contributions to the {W+ W- gamma gamma} and {W+ W- gamma Z0} vertices: -0.070GeV^{-2} < a_0/Lambda^2 < 0.070GeV^{-2}, -0.13GeV^{-2} < a_c/Lambda^2 < 0.19GeV^{-2}, -0.61GeV^{-2} < a_n/Lambda^2 < 0.57GeV^{-2}, where Lambda represents the energy scale for new physics., 23 pages, 6 figures, submitted to Phys. Letts. B
Published: 1999
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7. Intermittency and correlations in hadronic Z $^0$ decays

Author: K. Stephens, M. Schumacher, P. G. Estabrooks, F. Odorici, N. K. Watson, D. R. Rust, C. Littlewood, H. A. Neal, Otmar Biebel, P. Scharff-Hansen, P. M. Watkins, K. Hoffman, V. Gibson, Claire Shepherd-Themistocleous, A. M. Lee, J. Goldberg, Erez Etzion, Shlomit Tarem, B. Surrow, G. G. Hanson, Richard Teuscher, A. S. Turcot, N. Altekamp, H. Voss, A. Macpherson, H. O. Ogren, Christoph Geich-Gimbel, I. Trigger, F. Fiedler, Richard Keeler, D. R. Ward, A. M. Smith, P. I. Kayal, K. Stoll, G. Giacomelli, S. Yamashita, I. Lawson, R. J. Barlow, D. J. Miller, I. Cohen, Christoph Rembser, H. Mes, I. P. Duerdoth, S. Braibant, D. Axen, A. Jawahery, T. J. McMahon, A. De Roeck, M. Kobel, P. Igo-Kemenes, M. Hoch, K. Ishii, H. Jeremie, Dave Charlton, C. Couyoumtzelis, M. Fanti, S. A. Robins, M. S. Dixit, O. C. Cooke, S. Spagnolo, Andris Skuja, S. Petzold, Tetsuro Mashimo, A. A. Faust, Peter Sherwood, Alexander Wagner, R. Liebisch, K. Ackerstaff, Norbert Wermes, Sherry Towers, T. Kawamoto, Frans Meijers, J. Dubbert, P. Pfeifenschneider, M. F. Turner-Watson, I. J. Bloodworth, Vakhtang Kartvelishvili, P. Hüntemeyer, R. K. Carnegie, A. J. Martin, R. Kowalewski, J. E. Conboy, A. Fürtjes, R. Howard, P. E.L. Clarke, J. Ludwig, K. Runge, R. Mir, P. Bock, M. Kolrep, J. Patt, R. Hawkings, Satoshi Mihara, Paul Kyberd, S. Orito, S. Arcelli, M. Herndon, F. K. Loebinger, S. Baumann, J. A. Wilson, J. Böhme, Michael Hildreth, Alain Bellerive, André Schöning, Robert McPherson, J. P. Martin, O. Sahr, H. Landsman, P. Gagnon, J. Steuerer, Ivor Fleck, O. Schaile, S. Robertson, R. D. Heuer, E. A. Mckigney, Gideon Alexander, N. L. Rodning, W. Gorn, W. Mader, Paolo Capiluppi, Joleen Pater, P. Dervan, B. Poli, Peter R Hobson, S. De Jong, A. Klier, F. G. Oakham, A. Sittler, D. Zer-Zion, D. C. Imrie, C. K. Hargrove, S. Betts, Yoram Rozen, S. B. Anderson, Matthias Schröder, W. R. Gibson, Gregor Herten, R. L. Coxe, Georges Azuelos, K. Harder, Fabrizio Fabbri, A. Frey, H. Rick, E. L. Barberio, D. Lazic, A. Macchiolo, Zoltan Laszlo Trocsanyi, Dong Hee Kim, M. Hapke, A. Hocker, M. Thiergen, Gideon Bella, H. J. Burckhart, Jacqueline Batley, D. Chrisman, G. D. Long, E. Tsur, D. I. Futyan, Volker Blobel, R. J. Hemingway, T. Kuhl, J. Lauber, R. Van Kooten, S. M. Gascon-Shotkin, Paolo Giacomelli, Sven Menke, Christopher Hawkes, G. Yekutieli, M. Verzocchi, K. W. Bell, J. Pálinkás, J. Grunhaus, G. P. Siroli, M. Przybycień, Junichi Kanzaki, J. Polok, M. Boutemeur, F. S. Merritt, B. W. Kennedy, W. M. Sang, P. Jovanovic, Richard Nisius, D. Karlen, M. Hansroul, S. D. Talbot, Stan Bentvelsen, Christoph Schwick, T. Kress, M. J. Oreglia, J. E. Pilcher, Stephen Lloyd, Austin Ball, J. C. Hill, T. R. Junk, K. Graham, A. A. Carter, Ron Folman, P. S. Wells, B. List, Peter Krieger, Marco Cuffiani, Tara Shears, R. M. Brown, Ehud Duchovni, Lorne Levinson, Alessandro Montanari, W. J. McDonald, M. Jimack, B. C. Shen, A. M. Rossi, A. Biguzzi, J. G. Layter, F. Wäckerle, Terry Richard Wyatt, D. M. Gingrich, Randall Sobie, G. D. Lafferty, Giovanni Abbiendi, A. Michelini, J. R. Carter, C. R. Jones, Siegfried Bethke, D. Liu, A. K. Honma, W. G. Scott, T. Kobayashi, Juergen Thomas, J. Bechtluft, J. A. McKenna, Stefan Schmitt, G. N. Patrick, Daniele Bonacorsi, I. Nakamura, S. Rosati, R. J. Homer, C. Sbarra, F. R. Jacob, Sachio Komamiya, A. T. Watson, A. Harel, Ikuo Ueda, D. M. Strom, J. von Krogh, Guenter Duckeck, D. Glenzinski, J. Lu, Dezso Horvath, M. J. Losty, John Allison, T. P. Kokott, T. Saeki, Claudia Ciocca, K. Roscoe, Jean-Arcady Meyer, Klaus Kurt Desch, M. Gruwé, Shoji Asai, Alessandra Fanfani, R. Davis, E. Torrence, E. Clay, Achim Stahl, R. G. Kellogg, Daniel Lellouch, T. Behnke, Stefano Marcellini, A. W. Lloyd, Kiyotomo Kawagoe, G. W. Wilson, Takehiko Mori, D. E. Plane, P. Mättig, M. Hauschild, C. Markopoulos, G. M. Dallavalle, K. R. Hossain, James Pinfold, R. Perez-Ochoa, R. Seuster, J. Gascon, V. Zacek, M. A. Thomson, J. W. Gary, L. Brigliadori, Ekg Sarkisyan, E. K. U. Gross, Marcello Mannelli, M. Sproston, S. W. O'Neale, K. J. Anderson, Raimund Ströhmer, J. Letts, P. Poffenberger, German Martinez, Beatrix Dienes, J. M. Roney, C. Y. Chang, P. Taras, D. Lanske, Koichi Nagai, J. Schieck, W. Mohr, M. Fierro, S. R. Lautenschlager, K. Sachs, O. Runolfsson, Shlomo Dado, Claudio Grandi, J. S. White, Giora Mikenberg, S. F. Ashby, A. D. Schaile, Gabriella Pasztor, P. Vannerem, G. A. Snow, C. P. Ward, S. Söldner-Rembold, G. Gaycken, and P. G. Bright-Thomas
Subjects: Physics, Quantum chromodynamics, Particle physics, Annihilation, Physics and Astronomy (miscellaneous), Hadron, Monte Carlo method, Fizikai tudományok, Multiplicity (mathematics), Bose–Einstein correlations, law.invention, Nuclear physics, Természettudományok, law, Intermittency, High Energy Physics::Experiment, Engineering (miscellaneous), Cumulant, Particle Physics - Experiment
Abstract: A multidimensional study of local multiplicity fluctuations and multiparticle correlations of hadrons produced in Z decays is performed. The study is based on the data sample of more than 4 million events recorded with the OPAL detector at LEP. The fluctuations and correlations are analysed in terms of the normalized scaled factorial moments and cumulants up to the fifth order. The moments are observed to have intermittency-like behaviour, which is found to be more pronounced with increasing dimension. The large data sample allows for the first time a study of the factorial cumulants in e+e- annihilation. The analysis of the cumulants shows the existence of genuine multiparticle correlations with a strong intermittency rise up to higher orders. These correlations are found to be stronger in higher dimensions. The decomposition of the factorial moments into lower-order correlations that the dynamical fluctuations have important contributions from genuine many-particle correlations. The Monte Carlo models JETSET 7.4 and HERWIG 5.9 are found to reproduce the trend of the measured moments and cumulants but they underestimate the magnitudes. The results are found to be consistent with QCD jet formation dynamics, although additional contributions from other mechanisms in the hadronization process cannot be excluded. A multidimensional study of local multiplicity fluctuations and multiparticle correlations of hadrons produced in Z decays is performed. The study is based on the data sample of more than 4 million events recorded with the OPAL detector at LEP. The fluctuations and correlations are analysed in terms of the normalized scaled factorial moments and cumulants up to the fifth order. The moments are observed to have intermittency-like behaviour, which is found to be more pronounced with increasing dimension. The large data sample allows for the first time a study of the factorial cumulants in e+e- annihilation. The analysis of the cumulants shows the existence of genuine multiparticle correlations with a strong intermittency rise up to higher orders. These correlations are found to be stronger in higher dimensions. The decomposition of the factorial moments into lower-order correlations shows that the dynamical fluctuations have important contributions from genuine many-particle correlations. The Monte Carlo models JETSET 7.4 and HERWIG 5.9 are found to reproduce the trend of the measured moments and cumulants but they underestimate the magnitudes. The results are found to be consistent with QCD jet formation dynamics, although additional contributions from other mechanisms in the hadronization process cannot be excluded.
Published: 1999
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8. Search for scalar top and scalar bottom quarks at = 189 GeV at LEP

Author: G Abbiendi, K Ackerstaff, G Alexander, J Allison, N Altekamp, K.J Anderson, S Anderson, S Arcelli, S Asai, S.F Ashby, D Axen, G Azuelos, A.H Ball, E Barberio, R.J Barlow, J.R Batley, S Baumann, J Bechtluft, T Behnke, K.W Bell, G Bella, A Bellerive, S Bentvelsen, S Bethke, S Betts, O Biebel, A Biguzzi, V Blobel, I.J Bloodworth, P Bock, J Böhme, D Bonacorsi, M Boutemeur, S Braibant, P Bright-Thomas, L Brigliadori, R.M Brown, H.J Burckhart, P Capiluppi, R.K Carnegie, A.A Carter, J.R Carter, C.Y Chang, D.G Charlton, D Chrisman, C Ciocca, P.E.L Clarke, E Clay, I Cohen, J.E Conboy, O.C Cooke, C Couyoumtzelis, R.L Coxe, M Cuffiani, S Dado, G.M Dallavalle, R Davis, S De Jong, A de Roeck, P Dervan, K Desch, B Dienes, M.S Dixit, J Dubbert, E Duchovni, G Duckeck, I.P Duerdoth, P.G Estabrooks, E Etzion, F Fabbri, A Fanfani, M Fanti, A.A Faust, F Fiedler, M Fierro, I Fleck, R Folman, A Frey, A Fürtjes, D.I Futyan, P Gagnon, J.W Gary, J Gascon, S.M Gascon-Shotkin, G Gaycken, C Geich-Gimbel, G Giacomelli, P Giacomelli, V Gibson, W.R Gibson, D.M Gingrich, D Glenzinski, J Goldberg, W Gorn, C Grandi, K Graham, E Gross, J Grunhaus, M Gruwé, G.G Hanson, M Hansroul, M Hapke, K Harder, A Harel, C.K Hargrove, M Hauschild, C.M Hawkes, R Hawkings, R.J Hemingway, M Herndon, G Herten, R.D Heuer, M.D Hildreth, J.C Hill, P.R Hobson, M Hoch, A Hocker, K Hoffman, R.J Homer, A.K Honma, D Horváth, K.R Hossain, R Howard, P Hüntemeyer, P Igo-Kemenes, D.C Imrie, K Ishii, F.R Jacob, A Jawahery, H Jeremie, M Jimack, C.R Jones, P Jovanovic, T.R Junk, J Kanzaki, D Karlen, V Kartvelishvili, K Kawagoe, T Kawamoto, P.I Kayal, R.K Keeler, R.G Kellogg, B.W Kennedy, D.H Kim, A Klier, T Kobayashi, M Kobel, T.P Kokott, M Kolrep, S Komamiya, R.V Kowalewski, T Kress, P Krieger, J von Krogh, T Kuhl, P Kyberd, G.D Lafferty, H Landsman, D Lanske, J Lauber, S.R Lautenschlager, I Lawson, J.G Layter, A.M Lee, D Lellouch, J Letts, L Levinson, R Liebisch, B List, C Littlewood, A.W Lloyd, S.L Lloyd, F.K Loebinger, G.D Long, M.J Losty, J Lu, J Ludwig, D Liu, A Macchiolo, A Macpherson, W Mader, M Mannelli, S Marcellini, C Markopoulos, A.J Martin, J.P Martin, G Martinez, T Mashimo, P Mättig, W.J McDonald, J McKenna, E.A Mckigney, T.J McMahon, R.A McPherson, F Meijers, S Menke, F.S Merritt, H Mes, J Meyer, A Michelini, S Mihara, G Mikenberg, D.J Miller, R Mir, W Mohr, A Montanari, T Mori, K Nagai, I Nakamura, H.A Neal, R Nisius, S.W O'Neale, F.G Oakham, F Odorici, H.O Ogren, M.J Oreglia, S Orito, J Pálinkás, G Pásztor, J.R Pater, G.N Patrick, J Patt, R Perez-Ochoa, S Petzold, P Pfeifenschneider, J.E Pilcher, J Pinfold, D.E Plane, P Poffenberger, B Poli, J Polok, M Przybycień, C Rembser, H Rick, S Robertson, S.A Robins, N Rodning, J.M Roney, S Rosati, K Roscoe, A.M Rossi, Y Rozen, K Runge, O Runolfsson, D.R Rust, K Sachs, T Saeki, O Sahr, W.M Sang, E.K.G Sarkisyan, C Sbarra, A.D Schaile, O Schaile, P Scharff-Hansen, J Schieck, S Schmitt, A Schöning, M Schröder, M Schumacher, C Schwick, W.G Scott, R Seuster, T.G Shears, B.C Shen, C.H Shepherd-Themistocleous, P Sherwood, G.P Siroli, A Sittler, A Skuja, A.M Smith, G.A Snow, R Sobie, S Söldner-Rembold, S Spagnolo, M Sproston, A Stahl, K Stephens, J Steuerer, K Stoll, D Strom, R Ströhmer, B Surrow, S.D Talbot, P Taras, S Tarem, R Teuscher, M Thiergen, J Thomas, M.A Thomson, E Torrence, S Towers, I Trigger, Z Trócsányi, E Tsur, A.S Turcot, M.F Turner-Watson, I Ueda, R Van Kooten, P Vannerem, M Verzocchi, H Voss, F Wäckerle, A Wagner, C.P Ward, D.R Ward, P.M Watkins, A.T Watson, N.K Watson, P.S Wells, N Wermes, J.S White, G.W Wilson, J.A Wilson, T.R Wyatt, S Yamashita, G Yekutieli, V Zacek, and D Zer-Zion
Subjects: Quark, Nuclear and High Energy Physics, Top quark, Particle physics, High Energy Physics::Lattice, Nuclear Theory, FOS: Physical sciences, Fizikai tudományok, 7. Clean energy, 01 natural sciences, Bottom quark, High Energy Physics - Experiment, Charm quark, High Energy Physics - Experiment (hep-ex), Természettudományok, 0103 physical sciences, 010306 general physics, Physics, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Scalar (physics), Neutralino, High Energy Physics::Experiment, Neutrino, Particle Physics - Experiment, Lepton
Abstract: Searches for a scalar top quark and a scalar bottom quark have been performed using a data sample of 182 pb-1 at a centre-of-mass energy of 189 GeV collected with the OPAL detector at LEP. No evidence for a signal was found. The 95% confidence level lower limit on the scalar top quark mass is 90.3 GeV if the mixing angle between the supersymmetric partners of the left- and right-handed states of the top quark is zero. In the worst case, when the scalar top quark decouples from the Z boson, the lower limit is 87.2 GeV. These limits were obtained assuming that the scalar top quark decays into a charm quark and the lightest neutralino, and that the mass difference between the scalar top quark and the lightest neutralino is larger than 10 GeV. The complementary decay mode of the scalar top quark decaying into a bottom quark, a charged lepton and a scalar neutrino has also been studied. From a search for the scalar bottom quark, a mass limit of 88.6 GeV was obtained if the mass difference between the scalar bottom quark and the lightest neutralino is larger than 7 GeV. These limits significantly improve the previous OPAL limits., 18 pages, LaTeX, including 4 eps figures, submitted to Physics Letters B
Published: 1999
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9. Measurement of the semileptonic branching ratio of charm hadrons produced in ${\rm Z}^0\to{\rm c\bar c}$ decays

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., de Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, 010308 nuclear & particles physics, Branching fraction, Hadron, 01 natural sciences, 0103 physical sciences, Charm (quantum number), 010306 general physics, Engineering (miscellaneous), Particle Physics - Experiment, Lepton
Abstract: The inclusive charm hadron semileptonic branching fractions B(c to e) and B(c to mu) in Z to ccbar events have been determined using 4.4 million hadronic Z decays collected with the OPAL detector at LEP. A charm-enriched sample is obtained by selecting events with reconstructed D*+- mesons. Using leptons found in the hemisphere opposite that of the D*+- mesons, the semileptonic branching fractions of charm hadrons are measured to be B(c to e) = 0.103 +-0.009 +0.009 -0.008 and B(c to mu) = 0.090 +-0.007 +0.007 -0.006 where the first errors are in each case statistical and the others systematic. Combining these measurements, an inclusive semileptonic branching fraction of charm hadrons of B(c to l) = 0.095 +-0.006 +0.007 -0.006 is obtained. The inclusive charm hadron semileptonic branching fractions B(c to e) and B(c to mu) in Z to ccbar events have been determined using 4.4 million hadronic Z decays collected with the OPAL detector at LEP. A charm-enriched sample is obtained by selecting events with reconstructed D*+- mesons. Using leptons found in the hemisphere opposite that of the D*+- mesons, the semileptonic branching fractions of charm hadrons are measured to be B(c to e) = 0.103 +-0.009 +0.009 -0.008 and B(c to mu) = 0.090 +-0.007 +0.007 -0.006 where the first errors are in each case statistical and the others systematic. Combining these measurements, an inclusive semileptonic branching fraction of charm hadrons of B(c to l) = 0.095 +-0.006 +0.007 -0.006 is obtained.
Published: 1999
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10. Colour reconnection studies in e+e−→W+W− at GeV

Author: G. Abbiendi, K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, P. Bock, J. Böhme, D. Bonacorsi, M. Boutemeur, S. Braibant, P. Bright-Thomas, L. Brigliadori, R.M. Brown, H.J. Burckhart, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, C. Ciocca, P.E.L. Clarke, E. Clay, I. Cohen, J.E. Conboy, O.C. Cooke, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, G.M. Dallavalle, R. Davis, S. De Jong, A. de Roeck, P. Dervan, K. Desch, B. Dienes, M.S. Dixit, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, P.G. Estabrooks, E. Etzion, F. Fabbri, M. Fanti, A.A. Faust, F. Fiedler, M. Fierro, I. Fleck, R. Folman, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, W. Gorn, C. Grandi, K. Graham, E. Gross, J. Grunhaus, M. Gruwé, G.G. Hanson, M. Hansroul, M. Hapke, K. Harder, A. Harel, C.K. Hargrove, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, P.R. Hobson, M. Hoch, A. Hocker, K. Hoffman, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, D.C. Imrie, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, M. Jimack, C.R. Jones, P. Jovanovic, T.R. Junk, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, D.H. Kim, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, T. Kuhl, P. Kyberd, G.D. Lafferty, H. Landsman, D. Lanske, J. Lauber, S.R. Lautenschlager, I. Lawson, J.G. Layter, D. Lazic, A.M. Lee, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, D. Liu, A. Macchiolo, A. Macpherson, W. Mader, M. Mannelli, S. Marcellini, C. Markopoulos, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, J. Polok, M. Przybycień, C. Rembser, H. Rick, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, B. Schmitt, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Sittler, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, S. Spagnolo, M. Sproston, A. Stahl, K. Stephens, J. Steuerer, K. Stoll, D. Strom, R. Ströhmer, B. Surrow, S.D. Talbot, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, J. Thomas, M.A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, I. Ueda, R. Van Kooten, P. Vannerem, M. Verzocchi, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion
Subjects: Quantum chromodynamics, Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, Hadron, Observable, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Charged particle, 0103 physical sciences, Statistical precision, High Energy Physics::Experiment, Rapidity, Multiplicity (chemistry), 010306 general physics, Boson
Abstract: The predicted effects of final state interactions such as colour reconnection are investigated by measuring properties of hadronic decays of W bosons, recorded at a centre-of-mass energy of sqrt(s)=182.7 GeV in the OPAL detector at LEP. Dependence on the modelling of hadronic W decays is avoided by comparing W+W- -> qqqq events with the non-leptonic component of W+W- -> qqlnu events. The scaled momentum distribution, its mean value, x_p, and that of the charged particle multiplicity, n_ch, are measured and found to be consistent in the two channels. The measured differences are: Diff(x_p) = +0.7 +- 0.8 +- 0.6 and Diff(n_ch) = (-0.09 +- 0.09 +-0.05)*10**-2. In addition, measurements of rapidity and thrust are performed for W+W- -> qqqq events. The data are described well by standard QCD models and disfavour one model of colour reconnection within the ARIADNE program. The current implementation of the ELLIS-GEIGER model of colour reconnection is excluded. At the current level of statistical precision no evidence for colour reconnection effects was found in the observables studied. The predicted effect of colour reconnection on OPAL measurements of M_W is also quantified in the context of models studied.
Published: 1999
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11. Search for anomalous photonic events with missing energy in ${\rm e}^+{\rm e}^-$ collisions at $\sqrt{s}$ = 130, 136 and 183 GeV

Author: Sachio Komamiya, A. T. Watson, M. Boutemeur, F. S. Merritt, F. Scharf, T. P. Kokott, J. Letts, T. Saeki, Satoshi Mihara, German Martinez, J. Bechtluft, J. A. McKenna, G. G. Hanson, P. Scharff-Hansen, R. Davis, Randall Sobie, G. D. Lafferty, K. Sachs, S. Betts, M. Hapke, M. Fanti, G. Giacomelli, M. J. Oreglia, I. Lawson, Shlomo Dado, J. R. Carter, G. N. Patrick, A. M. Smith, Dave Charlton, R. Bartoldus, A. De Roeck, W. R. Gibson, H. O. Ogren, Christoph Geich-Gimbel, N. Altekamp, H. Voss, Guenter Duckeck, J. M. Roney, Robert McPherson, J. Grunhaus, S. R. Lautenschlager, K. Stoll, Andris Skuja, D. M. Strom, Gregor Herten, K. Harder, R. J. Barlow, G. Gaycken, P. G. Bright-Thomas, R. D. Heuer, D. J. Miller, Fabrizio Fabbri, D. C. Imrie, Claire Shepherd-Themistocleous, M. Schumacher, S. Petzold, R. Bürgin, O. Runolfsson, R. M. Brown, Lorne Levinson, M. S. Dixit, Frans Meijers, Giora Mikenberg, S. F. Ashby, Koichi Nagai, J. Schieck, Tetsuro Mashimo, Achim Stahl, Vakhtang Kartvelishvili, Paul Kyberd, J. E. Conboy, A. Fürtjes, C. Y. Chang, Ehud Duchovni, W. Mohr, M. Jimack, G. P. Siroli, J. E. Pilcher, F. Odorici, R. Van Kooten, T. R. Junk, A. Biguzzi, A. A. Faust, W. Gorn, P. Taras, F. K. Loebinger, P. S. Wells, Claudio Grandi, J. S. White, Christoph Schwick, A. Michelini, J. Steuerer, J. G. Layter, A. W. Lloyd, Ekg Sarkisyan, R. J. Hemingway, C. Hartmann, S. B. Anderson, D. E. Plane, Terry Richard Wyatt, Gideon Bella, K. Stephens, Stephen Hillier, H. A. Neal, G. M. Dallavalle, Ivor Fleck, G. W. Wilson, Satoshi Tanaka, Joleen Pater, A. D. Schaile, Gabriella Pasztor, M. Hauschild, C. Markopoulos, P. Vannerem, M. A. Thomson, A. Macpherson, H. J. Burckhart, Jacqueline Batley, F. Wäckerle, C. Littlewood, B. W. Kennedy, James Pinfold, R. Perez-Ochoa, R. Seuster, P. Jovanovic, A. Klier, Austin Ball, D. M. Gingrich, T. Kobayashi, E. K. U. Gross, L. Brigliadori, V. Gibson, H. Mes, S. M. Gascon-Shotkin, Peter Krieger, J. Gascon, R. Howard, Stan Bentvelsen, M. Sproston, K. Roscoe, G. A. Snow, C. P. Ward, Alessandro Montanari, D. Lanske, M. F. Turner-Watson, I. Trigger, I. P. Duerdoth, S. Braibant, A. Macchiolo, Peter R Hobson, D. R. Rust, P. E.L. Clarke, Klaus Kurt Desch, E. Torrence, M. Kobel, S. Söldner-Rembold, D. R. Ward, T. Kress, C. M. Hawkes, R. Mir, J. P. Martin, E. Clay, Otmar Biebel, R. Kowalewski, V. Zacek, R. Hawkings, S. W. O'Neale, K. J. Anderson, D. Zer-Zion, O. C. Cooke, P. Hüntemeyer, S. Arcelli, A. M. Lee, P. I. Kayal, Georges Azuelos, P. Pfeifenschneider, T. Kuhl, John Allison, J. W. Gary, Raimund Ströhmer, Norbert Wermes, E. von Törne, Sherry Towers, T. Kawamoto, S. De Jong, E. Tsur, D. S. Koetke, Marcello Mannelli, Richard Teuscher, A. S. Turcot, C. R. Jones, S. Orito, J. Patt, Richard Nisius, A. M. Rossi, André Schöning, P. Poffenberger, M. Fierro, M. Verzocchi, K. W. Bell, H. Rick, O. Sahr, F. G. Oakham, B. List, Marco Cuffiani, F. Fiedler, J. Pálinkás, Kiyotomo Kawagoe, B. Schmitt, E. L. Barberio, Gideon Alexander, Paolo Giacomelli, M. Hansroul, Paolo Capiluppi, J. C. Hill, Beatrix Dienes, C. Burgard, R. J. Homer, R. G. Kellogg, R. L. Coxe, W. J. McDonald, B. C. Shen, A. Hocker, M. Kolrep, Siegfried Bethke, D. Liu, A. K. Honma, D. Chrisman, G. D. Long, K. R. Hossain, Stefano Marcellini, Volker Blobel, W. G. Scott, I. Nakamura, Stephen Lloyd, W. M. Sang, Claudia Ciocca, D. Glenzinski, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, Michael Hildreth, Alain Bellerive, N. L. Rodning, C. Sbarra, F. R. Jacob, Daniele Bonacorsi, J. Lauber, J. von Krogh, S. D. Talbot, M. Gruwé, L. A. del Pozo, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, M. Herndon, D. Eatough, T. Behnke, M. Bobinski, J. A. Wilson, J. Böhme, D. Lazic, P. Gagnon, G. Yekutieli, M. Przybycień, A. A. Carter, Ron Folman, A. Sittler, Zoltan Laszlo Trocsanyi, Giovanni Abbiendi, S. D. Bird, D. Axen, A. Jawahery, Peter Sherwood, Stefan Schmitt, Alexander Wagner, J. Ludwig, K. Runge, P. Bock, Shoji Asai, P. G. Estabrooks, R. K. Keeler, Daniel Lellouch, N. K. Watson, Takehiko Mori, P. Mättig, P. M. Watkins, I. J. Bloodworth, S. Baumann, Yoram Rozen, E. A. Mckigney, J. Polok, D. Karlen, D. I. Futyan, J. Goldberg, B. Nellen, H. G. Evans, I. Cohen, Christoph Rembser, Erez Etzion, Stefan Kluth, Shlomit Tarem, B. Surrow, S. A. Robins, R. Liebisch, K. Ackerstaff, A. J. Martin, S. Yamashita, P. Igo-Kemenes, K. Ishii, H. Jeremie, W. Mader, O. Schaile, C. K. Hargrove, S. Robertson, Matthias Schröder, Sven Menke, M. Thiergen, and Tara Shears
Subjects: Physics, Particle physics, Missing energy, Physics and Astronomy (miscellaneous), Physics beyond the Standard Model, Standard Model, Nuclear physics, Pair production, Neutralino, High Energy Physics::Experiment, Gravitino, Production (computer science), Engineering (miscellaneous), Energy (signal processing)
Abstract: Photonic events with large missing energy have been observed in $\mathrm e^+e^-$ collisions at centre-of-mass energies of 130, 136 and 183 GeV collected in 1997 using the OPAL detector at LEP. Results are presented for event topologies with a single photon and missing transverse energy or with an acoplanar photon pair. Cross-section measurements are performed within the kinematic acceptance of each selection. These results are compared with the expectations from the Standard Model process ${\rm e}^+{\rm e}^-\to\nu\overline{\nu}$ + photon(s). No evidence is observed for new physics contributions to these final states. Using the data at $\sqrt{s}$ = 183 GeV, upper limits on ${\sigma({\rm e^+e^-}\to{\rm XY})\cdot{\rm BR}(\rm X \to Y \gamma)}$ and ${\sigma({\rm e^+e^-}\to{\rm XX})\cdot{\rm BR}^2(\rm X \to Y \gamma)}$ are derived for the case of stable and invisible Y. These limits apply to single and pair production of excited neutrinos ( $\rm X = \nu^*, Y = \nu$ ), to neutralino production ( $\rm X={{\tilde{\chi}}^{0}}_{2}, Y={{\tilde{\chi}}^{0}}_{1}$ ) and to supersymmetric models in which $\rm X = {{\tilde{\chi}}^{0}}_{1}$ and $\rm Y=\tilde{\mathrm{G}}$ is a light gravitino.
Published: 1999
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12. Measurements of flavour-dependent fragmentation functions in ${\bf Z^{0} \rightarrow{\rm q}\bar{\rm q}}$ events

Author: J. von Krogh, R. Bartoldus, G. Yekutieli, M. Przybycień, A. A. Carter, Ron Folman, J. Letts, M. Gruwé, L. A. del Pozo, P. G. Bright-Thomas, K. Stephens, M. Fanti, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, M. Herndon, Daniel Lellouch, M. Bobinski, C. Y. Chang, J. A. Wilson, J. Böhme, H. O. Ogren, K. Roscoe, M. Schumacher, E. Lefebvre, D. Lazic, Takehiko Mori, P. Mättig, F. Odorici, Randall Sobie, T. Schorner, S. D. Bird, John Allison, Reda Tafirout, Klaus Kurt Desch, G. D. Lafferty, Christoph Geich-Gimbel, S. M. Gascon-Shotkin, Achim Stahl, James Pinfold, R. Perez-Ochoa, R. Seuster, C. Littlewood, V. Gibson, E. Torrence, F. Scharf, K. Sachs, Shlomo Dado, Georges Azuelos, E. Tsur, German Martinez, J. Gascon, T. R. Junk, D. Axen, P. E.L. Clarke, A. Jawahery, Robert McPherson, M. Verzocchi, H. A. Neal, I. Trigger, E. Clay, K. W. Bell, R. G. Kellogg, J. Pálinkás, D. R. Ward, T. Kress, J. C. Hill, J. P. Martin, Dave Charlton, P. G. Estabrooks, Vakhtang Kartvelishvili, Mathieu Doucet, V. Zacek, T. Behnke, W. J. McDonald, Peter Sherwood, R. K. Keeler, B. C. Shen, Stefano Marcellini, M. F. Turner-Watson, J. W. Gary, R. D. Heuer, D. S. Koetke, W. R. Gibson, Stefan Schmitt, Siegfried Bethke, J. E. Conboy, R. Kowalewski, S. De Jong, Marcello Mannelli, Fabrizio Fabbri, M. A. Thomson, A. K. Honma, W. G. Scott, Guenter Duckeck, A. Fürtjes, N. K. Watson, W. M. Sang, Kiyotomo Kawagoe, Peter R Hobson, R. Bürgin, Alexander Wagner, I. Nakamura, E. K. U. Gross, H. Mes, P. Scharff-Hansen, A. M. Rossi, K. Nagai, I. P. Duerdoth, S. Braibant, J. Ludwig, D. Zer-Zion, K. Runge, P. Bock, P. M. Watkins, M. Sproston, A. Macchiolo, O. C. Cooke, Gregor Herten, P. Pfeifenschneider, H. Rick, Shoji Asai, Giora Mikenberg, A. Joly, R. M. Brown, Lorne Levinson, A. M. Smith, S. F. Ashby, K. R. Hossain, D. R. Rust, C. M. Hawkes, D. Glenzinski, J. Patt, André Schöning, K. Stoll, Andris Skuja, M. Boutemeur, F. S. Merritt, I. J. Bloodworth, P. Hüntemeyer, S. B. Anderson, P. Gagnon, S. Petzold, C. Sbarra, Satoshi Mihara, Gideon Alexander, Dezso Horvath, M. J. Losty, F. R. Jacob, Jean-Arcady Meyer, Tetsuro Mashimo, O. Sahr, Paolo Capiluppi, J. Grunhaus, C. Hartmann, D. E. Plane, A. M. Lee, Gideon Bella, A. D. Schaile, W. Gorn, Paul Kyberd, F. K. Loebinger, A. Sittler, Stephen Hillier, E. von Törne, Gabriella Pasztor, J. M. Roney, R. L. Coxe, Zoltan Laszlo Trocsanyi, Richard Nisius, Stan Bentvelsen, M. Fierro, G. M. Dallavalle, Yoram Rozen, H. J. Burckhart, Jacqueline Batley, P. Vannerem, Michael Hildreth, J. Steuerer, Ivor Fleck, Silvia Arcelli, J. Bechtluft, B. List, J. A. McKenna, D. Lui, A. Hocker, Paolo Giacomelli, Joleen Pater, Marco Cuffiani, Richard Teuscher, G. A. Snow, A. Klier, A. S. Turcot, F. Fiedler, D. Chrisman, G. D. Long, M. Hansroul, Ekg Sarkisyan, C. P. Ward, Sachio Komamiya, N. L. Rodning, R. Van Kooten, Theodoros Geralis, J. Lauber, J. Schieck, Volker Blobel, A. T. Watson, W. Mohr, G. G. Hanson, C. Burgard, S. Söldner-Rembold, B. Poli, R. J. Homer, T. P. Kokott, Stephen Lloyd, T. Saeki, G. Giacomelli, I. Lawson, F. Wäckerle, S. D. Talbot, J. E. Pilcher, D. M. Gingrich, Alessandra Fanfani, R. Davis, Claire Shepherd-Themistocleous, Ehud Duchovni, S. Baumann, J. Polok, A. De Roeck, M. Kobel, D. Karlen, M. Kolrep, D. Eatough, M. Jimack, C. R. Jones, G. W. Wilson, A. Michelini, H. M. Fischer, E. A. Mckigney, M. S. Dixit, D. C. Imrie, P. Vikas, A. A. Faust, Frans Meijers, Satoshi Tanaka, T. Kobayashi, D. Lanske, S. Betts, M. Hapke, G. P. Siroli, S. R. Lautenschlager, A. Biguzzi, J. G. Layter, Christoph Schwick, Claudia Ciocca, O. Runolfsson, D. I. Futyan, Claudio Grandi, M. J. Oreglia, A. W. Lloyd, S. Yamashita, P. Igo-Kemenes, S. A. Robins, K. Ishii, H. Jeremie, M. Hauschild, C. Markopoulos, R. Liebisch, K. Ackerstaff, J. R. Carter, G. N. Patrick, O. Schaile, Otmar Biebel, S. Robertson, P. Taras, Raimund Ströhmer, P. Poffenberger, Beatrix Dienes, Sven Menke, S. W. O'Neale, K. J. Anderson, P. I. Kayal, Erez Etzion, Stefan Kluth, Shlomit Tarem, Norbert Wermes, Sherry Towers, T. Kawamoto, S. Orito, J. Goldberg, B. Nellen, H. G. Evans, I. Cohen, Christoph Rembser, P. S. Wells, Terry Richard Wyatt, A. Macpherson, A. J. Martin, C. K. Hargrove, Tara Shears, R. Howard, R. Mir, R. Hawkings, J. S. White, Matthias Schröder, M. Thiergen, D. M. Strom, F. G. Oakham, B. Schmitt, E. L. Barberio, N. Altekamp, H. Voss, R. J. Barlow, D. J. Miller, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Austin Ball, Peter Krieger, and Alessandro Montanari
Subjects: Quark, Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, 010308 nuclear & particles physics, High Energy Physics::Lattice, Electron–positron annihilation, High Energy Physics::Phenomenology, Flavour, 01 natural sciences, Bottom quark, Charged particle, Nuclear physics, 0103 physical sciences, High Energy Physics::Experiment, Charm (quantum number), 010306 general physics, Maxima, Engineering (miscellaneous)
Abstract: Fragmentation functions for charged particles in ${\rm Z}^0 \rightarrow {\rm q}\bar{\rm q}$ events have been measured for bottom (b), charm (c) and light (uds) quarks as well as for all flavours together. The results are based on data recorded between 1990 and 1995 using the OPAL detector at LEP. Event samples with different flavour compositions were formed using reconstructed ${\rm D}^{*\pm}$ mesons and secondary vertices. The $\xi_{\rm p} =\ln(1/x_{\rm p})$ distributions and the position of their maxima $\xi_0$ are also presented separately for uds, c and b quark events. The fragmentation function for b quarks is significantly softer than for uds quarks.
Published: 1999
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13. Search for baryon and lepton number violating Z0 decays

Author: G. Abbiendi, K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, P. Bock, J. Böhme, D. Bonacorsi, M. Boutemeur, S. Braibant, P. Bright-Thomas, L. Brigliadori, R.M. Brown, H.J. Burckhart, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, C. Ciocca, P.E.L. Clarke, E. Clay, I. Cohen, J.E. Conboy, O.C. Cooke, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, G.M. Dallavalle, R. Davis, S. De Jong, A. de Roeck, P. Dervan, K. Desch, B. Dienes, M.S. Dixit, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, P.G. Estabrooks, E. Etzion, F. Fabbri, M. Fanti, A.A. Faust, F. Fiedler, M. Fierro, I. Fleck, R. Folman, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, W. Gorn, C. Grandi, K. Graham, E. Gross, J. Grunhaus, M. Gruwé, G.G. Hanson, M. Hansroul, M. Hapke, K. Harder, A. Harel, C.K. Hargrove, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, P.R. Hobson, M. Hoch, A. Hocker, K. Hoffman, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, D.C. Imrie, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, M. Jimack, C.R. Jones, P. Jovanovic, T.R. Junk, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, D.H. Kim, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, T. Kuhl, P. Kyberd, G.D. Lafferty, H. Landsman, D. Lanske, J. Lauber, S.R. Lautenschlager, I. Lawson, J.G. Layter, D. Lazic, A.M. Lee, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, D. Liu, A. Macchiolo, A. Macpherson, W. Mader, M. Mannelli, S. Marcellini, C. Markopoulos, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, J. Polok, M. Przybycień, C. Rembser, H. Rick, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, B. Schmitt, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Sittler, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, S. Spagnolo, M. Sproston, A. Stahl, K. Stephens, J. Steuerer, K. Stoll, D. Strom, R. Ströhmer, B. Surrow, S.D. Talbot, S. Tanaka, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, J. Thomas, M.A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, I. Ueda, R. Van Kooten, P. Vannerem, M. Verzocchi, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Detector, FOS: Physical sciences, Fizikai tudományok, Charge (physics), 01 natural sciences, Lepton number, High Energy Physics - Experiment, Baryon, High Energy Physics - Experiment (hep-ex), Természettudományok, 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Particle Physics - Experiment, Conjugate
Abstract: Using data collected with the OPAL detector at LEP, we have searched for the processes e+e- -> Z0 -> p e-, p mu- and the charge conjugate final-states. These would violate the conservation of the baryon-number B, lepton-number L and the fermion-number n = (B+L). No evidence for such decays has been found, and the 95% confidence level upper limits on the partial widths Z0 -> p e and Z0 -> p mu are found to be 4.6 and 4.4 keV respectively., 16 pages, LaTeX, 2 ps figs included, submitted to Physics Letters B
Published: 1999
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14. Multi-photon production in e+e− collisions at =183 GeV

Author: K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K.W. Bell, G. Bella, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, M. Bobinski, P. Bock, J. Böhme, M. Boutemeur, S. Braibant, P. Bright-Thomas, R.M. Brown, H.J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, C. Ciocca, P.E.L. Clarke, E. Clay, I. Cohen, J.E. Conboy, O.C. Cooke, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, G.M. Dallavalle, R. Davis, S. De Jong, L.A. del Pozo, A. de Roeck, K. Desch, B. Dienes, M.S. Dixit, M. Doucet, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, P.G. Estabrooks, E. Etzion, H.G. Evans, F. Fabbri, A. Fanfani, M. Fanti, A.A. Faust, F. Fiedler, M. Fierro, H.M. Fischer, I. Fleck, R. Folman, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, C. Geich-Gimbel, T. Geralis, G. Giacomelli, P. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, W. Gorn, C. Grandi, E. Gross, J. Grunhaus, M. Gruwé, G.G. Hanson, M. Hansroul, M. Hapke, C.K. Hargrove, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, S.J. Hillier, P.R. Hobson, A. Hocker, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, D.C. Imrie, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, M. Jimack, A. Joly, C.R. Jones, P. Jovanovic, T.R. Junk, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, P. Kyberd, G.D. Lafferty, D. Lanske, J. Lauber, S.R. Lautenschlager, I. Lawson, J.G. Layter, D. Lazic, A.M. Lee, E. Lefebvre, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, D. Liu, A. Macchiolo, A. Macpherson, M. Mannelli, S. Marcellini, C. Markopoulos, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, B. Poli, J. Polok, M. Przybycień, C. Rembser, H. Rick, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, B. Schmitt, S. Schmitt, A. Schöning, T. Schorner, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Sittler, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, M. Sproston, A. Stahl, K. Stephens, J. Steuerer, K. Stoll, D. Strom, R. Ströhmer, R. Tafirout, S.D. Talbot, S. Tanaka, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, M.A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, R. Van Kooten, P. Vannerem, M. Verzocchi, P. Vikas, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Luminosity (scattering theory), Photon, 010308 nuclear & particles physics, Branching fraction, Astrophysics::High Energy Astrophysical Phenomena, Resonance, Lambda, 01 natural sciences, 7. Clean energy, Excited state, 0103 physical sciences, High Energy Physics::Experiment, Invariant mass, 010306 general physics, Energy (signal processing)
Abstract: The process e+e- to gamma gamma (gamma) is studied using data recorded with the OPAL detector at LEP. The data sample corresponds to a total integrated luminosity of 56.2 pb-1 taken at a centre-of-mass energy of 183 GeV. The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Lambda+ > 233 GeV and Lambda- > 265 GeV as well as a mass limit for an excited electron, M(e*) > 227 GeV assuming equal e*egamma and eegamma couplings. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons.
Published: 1998
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15. Determination of the production rate of D*0 mesons and of the ratio V/(V+P) in $$Z^0 \to c\bar c$$ decays

Author: K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K. J. Anderson, S. Anderson, S. Arcelli, S. Asai, S. F. Ashby, D. Axen, G. Azuelos, A. H. Ball, E. Barberio, R. J. Barlow, R. Bartoldus, J. R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K. W. Bell, G. Bella, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S. D. Bird, V. Blobel, I. J. Bloodworth, M. Bobinski, P. Bock, D. Bonacorsi, M. Boutemeur, S. Braibant, L. Brigliadori, R. M. Brown, H. J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R. K. Carnegie, A. A. Carter, J. R.Carter, C. Y. Chang, D. G. Charlton, D. Chrisman, P. E. L. Clarke, I. Cohen, J. E. Conboy, O. C. Cooke, C. Couyoumtzelis, R. L. Coxe, M. Cuffiani, S. Dado, C. Dallapiccola, G. M. Dallavalle, R. Davis, S. De Jong, L. A. del Pozo, A. de Roeck, K. Desch, B. Dienes, M. S. Dixit, M. Doucet, E. Duchovni, G. Duckeck, I. P. Duerdoth, D. Eatough, P. G. Estabrooks, E. Etzion, H. G. Evans, M. Evans, F. Fabbri, A. Fanfani, M. Fanti, A. A. Faust, L. Feld, F. Fiedler, M. Fierro, H. M. Fischer, I. Fleck, R. Folman, D. G. Fong, M. Foucher, A. Fürtjes, D. I. Futyan, P. Gagnon, J. W. Gary, J. Gascon, S. M. Gascon-Shotkin, N. I. Geddes, C. Geich-Gimbel, T. Geralis, G. Giacomelli, P. Giacomelli, R. Giacomelli, V. Gibson, W. R. Gibson, D. M. Gingrich, D. Glenzinski, J. Goldberg, M. J. Goodrick, W. Gorn, C. Grandi, E. Gross, J. Grunhaus, M. Gruwé, C. Hajdu, G. G. Hanson, M. Hansroul, M. Hapke, C. K. Hargrove, P. A. Hart, C. Hartmann, M. Hauschild, C. M. Hawkes, R. Hawkings, R. J. Hemingway, M. Herndon, G. Herten, R. D. Heuer, M. D. Hildreth, J. C. Hill, S. J. Hillier, P. R. Hobson, A. Hocker, R. J. Homer, A. K. Honma, D. Horvath, K. R. Hossain, R. Howard, P. Hüntemeyer, D. E. Hutchcroft, P. Igo-Kemenes, D. C. Imrie, K. Ishii, A. Jawahery, P. W. Jeffreys, H. Jeremie, M. Jimack, A. Joly, C. R. Jones, M. Jones, U. Jost, P. Jovanovic, T. R. Junk, J. Kanzaki, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P. I. Kayal, R. K. Keeler, R. G. Kellogg, B. W. Kennedy, J. Kirk, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D. S. Koetke, T. P. Kokott, M. Kolrep, S. Komamiya, R. V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, P. Kyberd, G. D. Lafferty, R. Lahmann, W. P. Lai, D. Lanske, J. Lauber, S. R. Lautenschlager, I. Lawson, J. G. Layter, D. Lazic, A. M. Lee, E. Lefebvre, D. Lellouch, J. Letts, L. Levinson, B. List, S. L. Lloyd, F. K. Loebinger, G. D. Long, M. J. Losty, J. Ludwig, D. Lui, A. Macchiolo, A. Macpherson, M. Mannelli, S. Marcellini, C. Markopoulos, C. Markus, A. J. Martin, J. P. Martin, G. Martinez, T. Mashimo, P. Mättig, W. J. McDonald, J. McKenna, E. A. Mckigney, T. J. McMahon, R. A. McPherson, F. Meijers, S. Menke, F. S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D. J. Miller, A. Mincer, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H. A. Neal, B. Nellen, R. Nisius, S. W. O’Neale, F. G. Oakham, F. Odorici, H. O. Ogren, A. Oh, N. J. Oldershaw, M. J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J. R. Pater, G. N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J. E. Pilcher, J. Pinfold, D. E. Plane, P. Poffenberger, B. Poli, A. Posthaus, C. Rembser, S. Robertson, S. A. Robins, N. Rodning, J. M. Roney, A. Rooke, A. M. Rossi, P. Routenburg, Y. Rozen, K. Runge, O. Runolfsson, U. Ruppel, D. R. Rust, K. Sachs, T. Saeki, O. Sahr, W. M. Sang, E. K. G. Sarkisyan, C. Sbarra, A. D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, P. Schleper, B. Schmitt, S. Schmitt, A. Schöming, M. Schröder, M. Schumacher, C. Schwick, W. G. Scott, T. G. Shears, B. C. Shen, C. H. Shepherd-Themistocleous, P. Sherwood, G. P. Siroli, A. Sittler, A. Skillman, A. Skuja, A. M. Smith, G. A. Snow, R. Sobie, S. Söldner-Rembold, R. W. Springer, M. Sproston, K. Stephens, J. Steuerer, B. Stockhausen, K. Stoll, D. Strom, R. Ströhmer, P. Szymanski, R. Tafirout, S. D. Talbot, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, M. A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A. S. Turcot, M. F. Turner-Watson, I. Ueda, P. Utzat, R. Van Kooten, P. Vannerem, M. Verzocchi, P. Vikas, E. H. Vokurka, H. Voss, F. Wäckerle, A. Wagner, C. P. Ward, D. R. Ward, P. M. Watkins, A. T. Watson, N. K. Watson, P. S. Wells, N. Wermes, J. S. White, G. W. Wilson, J. A. Wilson, T. R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion
Subjects: Systematic error, Physics, Particle physics, Annihilation, Physics and Astronomy (miscellaneous), Meson, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Nuclear physics, Pseudoscalar, Excited state, High Energy Physics::Experiment, Nuclear Experiment, Engineering (miscellaneous), Production rate
Abstract: In e+e2212 collisions at centre-of-mass energies around 91 GeV, D*0 mesons have been reconstructed using data collected with the OPAL detector at LEP. The hadronisation fraction has been measured to be f(c→D*0)=0.218±0.054±0.045±0.007, where the errors correspond to the statistical and systematic errors specific to this analysis, and to systematic uncertainties from externally measured branching fractions, respectively. Together with previous OPAL measurements of the hadronisation fractions of other charmed mesons, this value is used to investigate the relative production of observed vector and pseudoscalar charmed mesons in $Z^0 \to c\bar c$ decays. The production ratio is determined to be PeffV = V/(V+P)=0.57±0.05. The relative primary production of vector and pseudoscalar mesons, Pvrim, is studied in the context of the production and decay of orbitally excited charmed resonances. The first measurement of the inclusive Ds*+ production rate in hadronic Z0 decays is presented.
Published: 1998
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16. An upper limit for the $\tau$ –neutrino mass from $\tau\rightarrow 5\pi^{\pm}\nu_{\tau}$ decays

Author: R. Bartoldus, H. M. Fischer, H. O. Ogren, Christoph Geich-Gimbel, P. G. Bright-Thomas, N. Altekamp, H. Voss, Gideon Bella, M. Schumacher, E. Lefebvre, S. B. Anderson, D. J. Miller, Vakhtang Kartvelishvili, S. L. Lloyd, F. Odorici, Otmar Biebel, P. I. Kayal, A. J. Martin, Norbert Wermes, Sherry Towers, T. Kawamoto, J. E. Conboy, A. Fürtjes, S. Orito, H. A. Neal, B. C. Shen, S. W. O'Neale, H. J. Burckhart, Jacqueline Batley, Stan Bentvelsen, J. A. McKenna, Daniel Lellouch, Takehiko Mori, J. Grunhaus, P. Gagnon, J. Allison, Siegfried Bethke, A. K. Honma, W. G. Scott, I. Nakamura, Silvia Arcelli, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, P. Mättig, R. Kowalewski, Austin Ball, Peter Krieger, C. K. Hargrove, Claudia Ciocca, M. Boutemeur, F. S. Merritt, Alessandro Montanari, S. A. Robins, H. Mes, I. P. Duerdoth, A. Sittler, R. Mir, Zoltan Laszlo Trocsanyi, Matthias Schröder, J. W. Gary, K. J. Anderson, R. Hawkings, Raimund Ströhmer, J. R. Carter, P. Igo-Kemenes, T. Schorner, M. Thiergen, S. Braibant, Gideon Alexander, Paolo Capiluppi, S. Baumann, K. Ishii, H. Jeremie, S. Betts, M. Hapke, Stefan Schmitt, J. Bechtluft, R. Liebisch, K. Ackerstaff, E. A. Mckigney, James Pinfold, R. Perez-Ochoa, R. Seuster, M. J. Oreglia, G. Duckeck, C. R. Jones, F. G. Oakham, D. Glenzinski, B. Schmitt, E. L. Barberio, G. N. Patrick, G. Mikenberg, P. Hüntemeyer, J. Gascon, V. Gibson, O. Schaile, Dezso Horvath, M. J. Losty, Ehud Duchovni, R. J. Barlow, Jean-Arcady Meyer, A. D. Schaile, Gabriella Pasztor, V. Zacek, K. Roscoe, W.J. McDonald, J. Lauber, S. Robertson, M. F. Turner-Watson, F. Scharf, M. Fierro, M. Jimack, Ekg Sarkisyan, R. G. Kellogg, T. Kobayashi, P. Vannerem, German Martinez, N. K. Watson, Tara Shears, D. Lui, S. M. Gascon-Shotkin, Shoji Asai, A. Michelini, Beatrix Dienes, Peter R Hobson, D. S. Koetke, Reda Tafirout, Klaus Kurt Desch, G. D. Lafferty, D. I. Futyan, Sven Menke, Marcello Mannelli, I. J. Bloodworth, E. Torrence, Richard Teuscher, A. S. Turcot, Dave Charlton, D. Zer-Zion, K. Stoll, G. A. Snow, Andris Skuja, J. Goldberg, Claire Shepherd-Themistocleous, Stefano Marcellini, F. Fiedler, B. Nellen, C. P. Ward, S. D. Talbot, S. Petzold, C. Y. Chang, E. Clay, Sachio Komamiya, R. L. Coxe, M. Przybzien, M. A. Thomson, Theodoros Geralis, G. W. Wilson, P. G. Estabrooks, R. K. Keeler, W. M. Sang, S. Söldner-Rembold, Tetsuro Mashimo, Yoram Rozen, P. Taras, A. Hocker, R. Bürgin, P. Vikas, E. K. U. Gross, D. Eatough, D. Chrisman, G. D. Long, D. Lanske, J. Letts, A. A. Faust, W. R. Gibson, Volker Blobel, S. R. Lautenschlager, M. Sproston, T. P. Kokott, P. M. Watkins, H. G. Evans, M. Kolrep, W. Gorn, T. Saeki, S. D. Bird, I. Cohen, Georges Azuelos, T. Behnke, E. Tsur, J. Polok, A. Joly, D. Karlen, O. Runolfsson, Christoph Rembser, Alessandra Fanfani, D. Axen, R. Davis, Satoru Yamashita, M. Verzocchi, K. W. Bell, A. M. Rossi, K. Sachs, Shlomo Dado, A. Jawahery, A. Macchiolo, Claudio Grandi, P. Scharff-Hansen, J. Pálinkás, R. M. Brown, C. M. Hawkes, C. Sbarra, Lorne Levinson, Stefan Kluth, Peter Sherwood, Alexander Wagner, Shlomit Tarem, J. M. Roney, J. C. Hill, F. R. Jacob, J. Ludwig, K. Runge, Richard Nisius, A. M. Smith, P. Bock, B. List, Marco Cuffiani, S. F. Ashby, J. Schieck, W. Mohr, C. Hartmann, D. E. Plane, Stephen Hillier, Paul Kyberd, F. K. Loebinger, G. M. Dallavalle, Michael Hildreth, J. Steuerer, Ivor Fleck, N. L. Rodning, B. Poli, Joleen Pater, A. Klier, P. Poffenberger, Satoshi Mihara, K. Stephens, C. Littlewood, G. Yekutieli, T. R. Junk, I. Trigger, D. R. Ward, T. Kress, A. A. Carter, Ron Folman, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, M. Herndon, M. Bobinski, J. A. Wilson, J. Böhme, P. E.L. Clarke, J. P. Martin, D. Lazic, S. De Jong, H. Rick, J. von Krogh, M. Gruwé, L. A. del Pozo, G. G. Hanson, G. Giacomelli, I. Lawson, A. De Roeck, M. Kobel, M. S. Dixit, Frans Meijers, O. C. Cooke, P. Pfeifenschneider, J. Patt, André Schöning, O. Sahr, A. Biguzzi, J. G. Layter, Paolo Giacomelli, M. Hansroul, C. Burgard, R. J. Homer, Achim Stahl, Kiyotomo Kawagoe, R. Van Kooten, K. R. Hossain, D. C. Imrie, G. P. Siroli, Christoph Schwick, F. Wäckerle, D. M. Gingrich, D. M. Strom, M. Fanti, Robert McPherson, Mathieu Doucet, R. D. Heuer, Fabrizio Fabbri, K. Nagai, Shigenori Tanaka, D. R. Rust, A. M. Lee, E. von Törne, P. S. Wells, Terry Richard Wyatt, A. T. Watson, A. Macpherson, R. J. Sobie, R. Howard, J. S. White, Gregor Herten, J. E. Pilcher, A. W. Lloyd, M. Hauschild, and C. Markopoulos
Subjects: Physics, Particle physics, Energy distribution, Physics and Astronomy (miscellaneous), High Energy Physics::Phenomenology, Particle identification, Nuclear physics, Tau neutrino, Pi, High Energy Physics::Experiment, Invariant mass, Limit (mathematics), Engineering (miscellaneous), ALEPH experiment
Abstract: An upper limit for the $\tau$–neutrino mass has been determined from the decay $\tau\rightarrow 5\pi^{\pm}\nu_{\tau}$ using data collected with the OPAL detector from 1991 to 1995 in $\rm e^{+}e^{-}$ collisions at $\sqrt{s}\approx M_\mathrm{Z}$. A limit of 43.2 MeV at 95% CL is obtained using a two–dimensional method in the $5\pi$ invariant mass and energy distribution from 22 selected events. Combining this result with OPAL's previously published measurement using $\rm \tau^{+}\tau^{-}\rightarrow 3h^{\pm}\bar{\nu}_{\tau}+3h^{\mp}\nu_{\tau}$ decays, a new combined limit of \(m_{\nu_{\tau}}
Published: 1998
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17. Bose-Einstein correlations of three charged pions in hadronic Z $^{\bf 0}$ decays

Author: Erez Etzion, Stefan Kluth, Shlomit Tarem, S. A. Robins, T. Schorner, J. Grunhaus, Tara Shears, R. Liebisch, K. Ackerstaff, Sachio Komamiya, Theodoros Geralis, A. T. Watson, T. P. Kokott, T. Saeki, Alessandra Fanfani, G. Yekutieli, Otmar Biebel, G. G. Hanson, W. R. Gibson, H. M. Fischer, M. Przybycień, M. F. Turner-Watson, Peter R Hobson, J. Goldberg, D. Zer-Zion, M. Fierro, B. Nellen, S. R. Lautenschlager, A. A. Carter, Ron Folman, G. Giacomelli, I. Lawson, M. Boutemeur, F. S. Merritt, H. G. Evans, Gideon Bella, H. J. Burckhart, I. Cohen, Christoph Rembser, A. De Roeck, M. Kobel, O. Runolfsson, M. S. Dixit, Frans Meijers, J. Letts, R. M. Brown, Lorne Levinson, Matthias Schröder, A. W. Lloyd, P. I. Kayal, P. Gagnon, W. M. Sang, Jacqueline Batley, Claudio Grandi, M. Thiergen, J. Bechtluft, J. A. McKenna, Satoshi Mihara, Ekg Sarkisyan, P. E.L. Clarke, S. Yamashita, Kiyotomo Kawagoe, J. P. Martin, Ehud Duchovni, K. Sachs, K. Roscoe, J. von Krogh, M. Hauschild, C. Markopoulos, Norbert Wermes, Sherry Towers, S. De Jong, A. Sittler, Shlomo Dado, T. Kawamoto, Zoltan Laszlo Trocsanyi, P. Vikas, M. Jimack, Claire Shepherd-Themistocleous, P. Igo-Kemenes, P. G. Estabrooks, N. K. Watson, M. Gruwé, Reda Tafirout, Klaus Kurt Desch, A. J. Martin, H. Rick, R. Bartoldus, G. W. Wilson, A. Joly, D. Lanske, S. Orito, L. A. del Pozo, Claudia Ciocca, K. Ishii, H. Jeremie, A. Michelini, E. Torrence, Achim Stahl, E. Clay, H. O. Ogren, S. Betts, M. Hapke, Giora Mikenberg, Satoshi Tanaka, T. Kobayashi, P. M. Watkins, Georges Azuelos, K. Stephens, S. D. Bird, C. Sbarra, F. R. Jacob, E. Tsur, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, M. Herndon, C. K. Hargrove, K. Nagai, Michael Hildreth, M. Bobinski, J. A. Wilson, S. F. Ashby, K. R. Hossain, N. L. Rodning, J. Böhme, A. D. Schaile, Gabriella Pasztor, C. Hartmann, Christoph Geich-Gimbel, P. S. Wells, Vakhtang Kartvelishvili, P. Vannerem, M. Verzocchi, K. W. Bell, J. Pálinkás, J. C. Hill, O. Schaile, B. Poli, D. Axen, A. Jawahery, Stefan Schmitt, C. Littlewood, A. Biguzzi, D. E. Plane, R. L. Coxe, Silvia Arcelli, M. J. Oreglia, Stephen Hillier, D. Lui, Paul Kyberd, F. K. Loebinger, J. G. Layter, J. E. Conboy, G. M. Dallavalle, A. Fürtjes, James Pinfold, R. Perez-Ochoa, R. Seuster, W. J. McDonald, B. C. Shen, V. Gibson, D. Lazic, G. A. Snow, C. P. Ward, A. Hocker, Terry Richard Wyatt, D. R. Rust, C. R. Jones, J. Steuerer, Ivor Fleck, J. R. Carter, G. N. Patrick, Siegfried Bethke, A. K. Honma, W. G. Scott, Randall Sobie, S. M. Gascon-Shotkin, S. Söldner-Rembold, S. Baumann, S. Robertson, Joleen Pater, D. Chrisman, G. D. Long, Peter Sherwood, G. D. Lafferty, Gregor Herten, T. R. Junk, S. W. O'Neale, I. Nakamura, A. Klier, E. A. Mckigney, Volker Blobel, Alexander Wagner, I. Trigger, K. J. Anderson, Sven Menke, A. M. Rossi, J. Ludwig, Raimund Ströhmer, D. R. Ward, N. Altekamp, H. Voss, K. Runge, T. Kress, P. Bock, D. Glenzinski, Dezso Horvath, M. J. Losty, J. M. Roney, J. Lauber, Stephen Lloyd, J. E. Pilcher, Jean-Arcady Meyer, Dave Charlton, D. I. Futyan, R. J. Barlow, A. M. Lee, D. J. Miller, J. Gascon, P. Poffenberger, D. C. Imrie, John Allison, D. M. Strom, E. von Törne, R. Bürgin, S. D. Talbot, Guenter Duckeck, Paolo Giacomelli, R. Kowalewski, D. Eatough, G. P. Siroli, Shoji Asai, M. Hansroul, Christoph Schwick, Beatrix Dienes, C. Burgard, R. G. Kellogg, M. Fanti, Gideon Alexander, R. J. Homer, Paolo Capiluppi, S. B. Anderson, Daniel Lellouch, R. Mir, C. Y. Chang, R. Hawkings, A. Macpherson, Stefano Marcellini, Richard Keeler, O. C. Cooke, J. W. Gary, Takehiko Mori, P. Taras, P. Pfeifenschneider, Robert McPherson, R. Howard, D. S. Koetke, J. S. White, Mathieu Doucet, J. Patt, André Schöning, P. Mättig, R. D. Heuer, Fabrizio Fabbri, Marcello Mannelli, O. Sahr, Stan Bentvelsen, R. Van Kooten, K. Stoll, V. Zacek, F. Wäckerle, Andris Skuja, D. M. Gingrich, S. Petzold, Tetsuro Mashimo, Richard Teuscher, A. S. Turcot, F. Fiedler, F. G. Oakham, W. Gorn, B. Schmitt, E. L. Barberio, M. Kolrep, I. J. Bloodworth, P. Scharff-Hansen, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Austin Ball, Yoram Rozen, Peter Krieger, Alessandro Montanari, A. M. Smith, J. Polok, D. Karlen, A. A. Faust, T. Behnke, A. Macchiolo, C. M. Hawkes, Richard Nisius, B. List, Marco Cuffiani, H. Mes, I. P. Duerdoth, S. Braibant, P. Hüntemeyer, R. Davis, P. G. Bright-Thomas, M. Schumacher, E. Lefebvre, F. Odorici, H. A. Neal, F. Scharf, German Martinez, M. A. Thomson, E. K. U. Gross, M. Sproston, J. Schieck, and W. Mohr
Subjects: Physics, Particle physics, Physics and Astronomy (miscellaneous), High Energy Physics::Phenomenology, Nuclear Theory, Hadron, Bose–Einstein correlations, Lambda, Nuclear physics, Near threshold, Pion, Coulomb, High Energy Physics::Experiment, Nuclear Experiment, Coulomb effect, Engineering (miscellaneous)
Abstract: Bose-Einstein Correlations (BEC) of three identical charged pions were studied in $4 \times 10^6$ hadronic ${\rm Z}^0$ decays recorded with the OPAL detector at LEP. The genuine three-pion correlations, corrected for the Coulomb effect, were separated from the known two-pion correlations by a new subtraction procedure. A significant genuine three-pion BEC enhancement near threshold was observed having an emitter source radius of $r_3 = 0.580 \pm 0.004 \mbox{ (stat.)} \pm 0.029 \mbox{ (syst.)} \mbox{ fm}$ and a strength of $\lambda_3 = 0.504 \pm 0.010 \mbox{ (stat.)}\pm 0.041 \mbox{ (syst.)}$ . The Coulomb correction was found to increase the $\lambda_3$ value by $\sim $ 9% and to reduce $r_3$ by $\sim $ 6%. The measured $\lambda_3$ corresponds to a value of $0.707 \pm 0.014 \mbox{ (stat.)} \pm 0.078 \mbox{ (syst.)}$ when one takes into account the three-pion sample purity. A relation between the two-pion and the three-pion source parameters is discussed.
Published: 1998
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18. An upper limit on the anomalous magnetic moment of the τ lepton

Author: K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K.W. Bell, G. Bella, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, M. Bobinski, P. Bock, D. Bonacorsi, M. Boutemeur, S. Braibant, L. Brigliadori, R.M. Brown, H.J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, P.E.L. Clarke, I. Cohen, J.E. Conboy, O.C. Cooke, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, C. Dallapiccola, G.M. Dallavalle, R. Davis, S. De Jong, L.A. del Pozo, A. de Roeck, K. Desch, B. Dienes, M.S. Dixit, M. Doucet, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, P.G. Estabrooks, E. Etzion, H.G. Evans, M. Evans, F. Fabbri, A. Fanfani, M. Fanti, A.A. Faust, L. Feld, F. Fiedler, M. Fierro, H.M. Fischer, I. Fleck, R. Folman, D.G. Fong, M. Foucher, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, N.I. Geddes, C. Geich-Gimbel, T. Geralis, G. Giacomelli, P. Giacomelli, R. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, M.J. Goodrick, W. Gorn, C. Grandi, E. Gross, J. Grunhaus, M. Gruwé, C. Hajdu, G.G. Hanson, M. Hansroul, M. Hapke, C.K. Hargrove, P.A. Hart, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, S.J. Hillier, P.R. Hobson, A. Hocker, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, D.E. Hutchcroft, P. Igo-Kemenes, D.C. Imrie, K. Ishii, A. Jawahery, P.W. Jeffreys, H. Jeremie, M. Jimack, A. Joly, C.R. Jones, M. Jones, U. Jost, P. Jovanovic, T.R. Junk, J. Kanzaki, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, J. Kirk, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, P. Kyberd, G.D. Lafferty, R. Lahmann, W.P. Lai, D. Lanske, J. Lauber, S.R. Lautenschlager, I. Lawson, J.G. Layter, D. Lazic, A.M. Lee, E. Lefebvre, D. Lellouch, J. Letts, L. Levinson, B. List, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, D. Lui, A. Macchiolo, A. Macpherson, M. Mannelli, S. Marcellini, C. Markopoulos, C. Markus, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, A. Mincer, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, A. Oh, N.J. Oldershaw, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, B. Poli, A. Posthaus, C. Rembser, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, A. Rooke, A.M. Rossi, P. Routenburg, Y. Rozen, K. Runge, O. Runolfsson, U. Ruppel, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, P. Schleper, B. Schmitt, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, R.P.B. Sieberg, G.P. Siroli, A. Sittler, A. Skillman, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, R.W. Springer, M. Sproston, K. Stephens, J. Steuerer, B. Stockhausen, K. Stoll, D. Strom, R. Ströhmer, P. Szymanski, R. Tafirout, S.D. Talbot, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, M.A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, I. Ueda, P. Utzat, R. Van Kooten, P. Vannerem, M. Verzocchi, P. Vikas, E.H. Vokurka, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Anomalous magnetic dipole moment, 010308 nuclear & particles physics, Form factor (quantum field theory), 01 natural sciences, High Energy Physics - Experiment, Dipole, 0103 physical sciences, Magnetic form factor, Radiative transfer, Vertex (curve), High Energy Physics::Experiment, Production (computer science), 010306 general physics, Particle Physics - Experiment, Lepton
Abstract: Using radiative Z^0 -> \tau^+ \tau^- \gamma events collected with the OPAL detector at LEP at \sqrt{s}= M_Z during 1990-95, a direct study of the electromagnetic current at the \tau\gamma vertex has been performed in terms of the anomalous magnetic form factor F_2 of the \tau lepton. The analysis is based on a data sample of 1429 e^+ e^- -> \tau^+ \tau^- \gamma events which are examined for a deviation from the expectation with F_2 = 0. From the non-observation of anomalous \tau^+ \tau^- \gamma production a limit of -0.068 < F_2 < 0.065 is obtained. This can also be interpreted as a limit on the electric dipole form factor F_3 as -3.8 x 10^-16 e-cm < eF_3 < 3.6 x 10^-16 e-cm. The above ranges are valid at the 95% confidence level., Comment: 20 pages, LaTeX, uses a4p.sty, 4 eps figures included, submitted to Phys. Lett. B
Published: 1998
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19. Search for an excess in the production of four-jet events from e+e− collisions at =130–184 GeV

Author: K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K.W. Bell, G. Bella, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, M. Bobinski, P. Bock, D. Bonacorsi, M. Boutemeur, S. Braibant, L. Brigliadori, R.M. Brown, H.J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, P.E.L. Clarke, I. Cohen, J.E. Conboy, O.C. Cooke, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, C. Dallapiccola, G.M. Dallavalle, R. Davis, S. De Jong, L.A. del Pozo, A. de Roeck, K. Desch, B. Dienes, M.S. Dixit, M. Doucet, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, P.G. Estabrooks, E. Etzion, H.G. Evans, M. Evans, F. Fabbri, A. Fanfani, M. Fanti, A.A. Faust, L. Feld, F. Fiedler, M. Fierro, H.M. Fischer, I. Fleck, R. Folman, D.G. Fong, M. Foucher, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, N.I. Geddes, C. Geich-Gimbel, T. Geralis, G. Giacomelli, P. Giacomelli, R. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, M.J. Goodrick, W. Gorn, C. Grandi, E. Gross, J. Grunhaus, M. Gruwé, C. Hajdu, G.G. Hanson, M. Hansroul, M. Hapke, C.K. Hargrove, P.A. Hart, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, S.J. Hillier, P.R. Hobson, A. Hocker, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, D.E. Hutchcroft, P. Igo-Kemenes, D.C. Imrie, K. Ishii, A. Jawahery, P.W. Jeffreys, H. Jeremie, M. Jimack, A. Joly, C.R. Jones, M. Jones, U. Jost, P. Jovanovic, T.R. Junk, J. Kanzaki, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, J. Kirk, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, P. Kyberd, G.D. Lafferty, R. Lahmann, W.P. Lai, D. Lanske, J. Lauber, S.R. Lautenschlager, I. Lawson, J.G. Layter, D. Lazic, A.M. Lee, E. Lefebvre, D. Lellouch, J. Letts, L. Levinson, B. List, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, D. Lui, A. Macchiolo, A. Macpherson, M. Mannelli, S. Marcellini, C. Markopoulos, C. Markus, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, A. Mincer, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, A. Oh, N.J. Oldershaw, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, B. Poli, A. Posthaus, C. Rembser, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, A. Rooke, A.M. Rossi, P. Routenburg, Y. Rozen, K. Runge, O. Runolfsson, U. Ruppel, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, P. Schleper, B. Schmitt, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Sittler, A. Skillman, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, R.W. Springer, M. Sproston, K. Stephens, J. Steuerer, B. Stockhausen, K. Stoll, D. Strom, R. Ströhmer, P. Szymanski, R. Tafirout, S.D. Talbot, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, M.A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, I. Ueda, P. Utzat, R. Van Kooten, P. Vannerem, M. Verzocchi, P. Vikas, E.H. Vokurka, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Aleph, 010308 nuclear & particles physics, FOS: Physical sciences, Jet (particle physics), 01 natural sciences, High Energy Physics - Experiment, Standard Model, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, High Energy Physics::Experiment, Production (computer science), 010306 general physics, Particle Physics - Experiment
Abstract: Events with four distinct jets from e^+e^- collisions, collected by the OPAL detector at centre-of-mass energies between 130 and 184 GeV, are analysed for a peak in the sum of dijet masses. This search is motivated by the ALEPH Collaboration's observation of a clear excess of events with dijet mass sums close to 105 GeV in data taken at centre-of-mass energies of 130 and 136 GeV in 1995. We have observed no significant excess of four-jet events compared to the Standard Model expectation for any dijet mass sum at any energy. Our observation is inconsistent with the excess observed by ALEPH in 1995. Upper limits are determined on the production cross-section as a function of the dijet mass sum., Comment: 24 pages, LaTeX, uses a4p.sty, 5 eps figures included, submitted to Physics Letters B
Published: 1998
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20. Production of ${\rm f_0}(980)$ , ${\rm f}_2(1270)$ and $\phi(1020)$ in hadronic ${\rm Z}^0$ decay

Author: S. Betts, S. Yamashita, M. Hapke, J. Letts, P. Igo-Kemenes, D. E. Hutchcroft, K. Ishii, H. Jeremie, K. Sachs, A. Biguzzi, A. Rooke, J. G. Layter, Paolo Giacomelli, P. S. Wells, M. J. Oreglia, Shlomo Dado, O. Schaile, M. Hansroul, S. R. Lautenschlager, Terry Richard Wyatt, R. Lahmann, D. C. Imrie, L. Brigliadori, Sven Menke, Gideon Bella, T. Behnke, J. R. Carter, C. Burgard, G. N. Patrick, Stefan Schmitt, C. Hartmann, D. E. Plane, Stephen Hillier, G. M. Dallavalle, H. J. Burckhart, Jacqueline Batley, H. M. Fischer, R. J. Hemingway, Giora Mikenberg, S. F. Ashby, R. W. Springer, A. Macpherson, G. P. Siroli, Otmar Biebel, R. J. Homer, B. W. Kennedy, Christoph Schwick, A. Macchiolo, Tara Shears, P. Jovanovic, C. R. Jones, W. M. Sang, Austin Ball, O. Runolfsson, N. J. Oldershaw, J. Lauber, C. M. Hawkes, Peter Krieger, P. A. Hart, Kiyotomo Kawagoe, S. W. O'Neale, Georges Azuelos, Shoji Asai, G. G. Hanson, G. Yekutieli, E. Tsur, M. Boutemeur, F. S. Merritt, K. J. Anderson, M. Verzocchi, Richard Nisius, Alessandro Montanari, Richard Teuscher, A. D. Schaile, K. W. Bell, P. I. Kayal, J. Pálinkás, Gabriella Pasztor, H. A. Neal, R. Howard, M. F. Turner-Watson, J. S. White, A. S. Turcot, F. Fiedler, G. Giacomelli, J. C. Hill, B. List, I. Lawson, Daniel Lellouch, C. Y. Chang, W. J. McDonald, Dave Charlton, A. De Roeck, P. Vannerem, U. Ruppel, A. A. Carter, Marco Cuffiani, Norbert Wermes, B. C. Shen, Peter R Hobson, H. Mes, Ron Folman, P. Taras, G. W. Wilson, D. Zer-Zion, D. Lui, K. R. Hossain, R. Bürgin, Michael Kobel, Siegfried Bethke, A. K. Honma, M. Hauschild, C. Markopoulos, U. Jost, R. Mir, R. Hawkings, M. S. Dixit, I. P. Duerdoth, W. G. Scott, Sherry Towers, I. Nakamura, C. Markus, Frans Meijers, T. Kawamoto, Claudio Grandi, S. Braibant, P. Utzat, P. Routenburg, Matthias Schröder, E. H. Vokurka, P. E.L. Clarke, J. Grunhaus, Allen Mincer, M. K. Jones, Erez Etzion, Stefan Kluth, Shlomit Tarem, Takehiko Mori, P. Mättig, J. P. Martin, G. A. Snow, C. P. Ward, A. Joly, V. Zacek, D. Glenzinski, Dezso Horvath, M. J. Losty, S. Robertson, Julie Kirk, M. Thiergen, Gregor Herten, Jean-Arcady Meyer, Ikuo Ueda, D. M. Strom, S. Orito, J. Bechtluft, Raimund Ströhmer, Daniele Bonacorsi, R. L. Coxe, S. De Jong, P. G. Estabrooks, R. K. Keeler, N. K. Watson, P. M. Watkins, S. D. Talbot, F. G. Oakham, B. Schmitt, O. C. Cooke, Claire Shepherd-Themistocleous, P. Pfeifenschneider, M. Kolrep, E. L. Barberio, J. A. McKenna, J. E. Pilcher, S. Söldner-Rembold, P. Hüntemeyer, C. Sbarra, D. Eatough, Sachio Komamiya, C. Dallapiccola, P. Poffenberger, Theodoros Geralis, A. T. Watson, Randall Sobie, G. D. Lafferty, J. Patt, André Schöning, J. von Krogh, A. A. Faust, S. A. Robins, O. Sahr, N. Altekamp, H. Voss, T. P. Kokott, M. Gruwé, R. J. Barlow, T. Saeki, D. J. Miller, R. Bartoldus, A. J. Martin, R. Davis, L. A. del Pozo, B. Stockhausen, Paul Kyberd, F. K. Loebinger, Alessandra Fanfani, K. Ackerstaff, P. Scharff-Hansen, T. J. McMahon, Beatrix Dienes, I. J. Bloodworth, A. Hocker, H. O. Ogren, J. Steuerer, C. Couyoumtzelis, Ivor Fleck, Silvia Arcelli, M. Schumacher, E. Lefebvre, S. M. Gascon-Shotkin, R. K. Carnegie, Guenter Duckeck, Satoshi Mihara, Joleen Pater, M. Herndon, Christoph Geich-Gimbel, A. Klier, M. Bobinski, J. A. Wilson, C. K. Hargrove, R. Giacomelli, A. Oh, F. Odorici, M. Fierro, P. Gagnon, S. Baumann, Ekg Sarkisyan, Yoram Rozen, S. B. Anderson, M. Foucher, D. Chrisman, G. D. Long, D. Lazic, Matthew Evans, A. M. Rossi, John Allison, P. Szymanski, E. A. Mckigney, P. W. Jeffreys, W. P. Lai, Vakhtang Kartvelishvili, K. Stephens, Junichi Kanzaki, R. G. Kellogg, J. E. Conboy, A. Fürtjes, Csaba Hajdu, D. Karlen, A. Sittler, Stefano Marcellini, J. Goldberg, J. M. Roney, Stan Bentvelsen, Lutz Feld, N. I. Geddes, Peter Schleper, Michael Hildreth, V. Gibson, N. L. Rodning, Zoltan Laszlo Trocsanyi, B. Poli, D. I. Futyan, B. Nellen, Volker Blobel, T. R. Junk, P. Vikas, D. Lanske, I. Trigger, D. R. Ward, T. Kress, A. M. Smith, S. D. Bird, D. Axen, A. Jawahery, H. G. Evans, Peter Sherwood, M. J. Goodrick, I. Cohen, Christoph Rembser, Alexander Wagner, J. Ludwig, K. Runge, P. Bock, Stephen Lloyd, James Pinfold, R. Perez-Ochoa, D. G. Fong, J. Gascon, Ehud Duchovni, M. Jimack, J. W. Gary, D. S. Koetke, A. Michelini, Marcello Mannelli, K. Stoll, Andris Skuja, T. Kobayashi, S. Petzold, Tetsuro Mashimo, W. Gorn, R. Kowalewski, R. Van Kooten, Gideon Alexander, Paolo Capiluppi, F. Wäckerle, D. M. Gingrich, M. Fanti, W. R. Gibson, Robert McPherson, Mathieu Doucet, R. M. Brown, Lorne Levinson, A. Skillman, R. D. Heuer, Reda Tafirout, Klaus Kurt Desch, Fabrizio Fabbri, E. Torrence, K. Nagai, D. R. Rust, A. M. Lee, E. von Törne, F. Scharf, German Martinez, M. A. Thomson, E. K. U. Gross, M. Sproston, J. Schieck, W. Mohr, and A. Posthaus
Subjects: Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, Hadron, Fragmentation function, High Energy Physics::Experiment, Channel analysis, Scalar meson, Engineering (miscellaneous)
Abstract: Inclusive production of the ${\rm f_0}(980)$, ${\rm f}_2(1270)$ and $\phi(1020)$ resonances has been studied in a sample of 4.3 million hadronic ${\rm Z}^0$ decays from the OPAL experiment at LEP. A coupled channel analysis has been used for the ${\rm f}_0$ in simultaneous fits to the resonances in inclusive $\pi^+\pi^-$ and ${\rm K^+K^-}$ mass spectra. Fragmentation functions are reported for the three states. Total inclusive rates are measured to be $0.141 \pm 0.007 \pm 0.011$${\rm f}_0$, $0.155\pm0.011\pm0.018$${\rm f}_2$ and $0.091\pm0.002\pm0.003$$\phi$ mesons per hadronic ${\rm Z}^0$ decay. The production properties of the ${\rm f}_0$, including those in three-jet events, are compared with those of the ${\rm f}_2$ and $\phi$, and with the Lund string model of hadron production. All measurements are consistent with the hypothesis that the ${\rm f_0}(980)$ is a conventional ${\rm q\bar q}$ scalar meson.
Published: 1998
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21. Search for anomalous production of photonic events with missing energy in ${\rm e^+e^-}$ collisions at $\sqrt{s} = 130$ –172 GeV

Author: A. Klier, P. Routenburg, C. Dallapiccola, M. Hauschild, C. Markopoulos, C. Markus, G. T. Jones, E. H. Vokurka, N. Altekamp, H. Voss, S. Orito, W. Gorn, S. R. Lautenschlager, H. A. Neal, R. J. Barlow, D. J. Miller, Stefan Kluth, E. K.G. Sarkisyan, U. Ruppel, M. R. Ingram, J. Lauber, S. Betts, M. Hapke, W. J. McDonald, A. Sittler, P. G. Estabrooks, O. Runolfsson, G. W. Wilson, V. Zacek, D. E. Hutchcroft, N. J. Oldershaw, Gideon Bella, R. Howard, U. Jost, N. K. Watson, S. D. Talbot, G. Yekutieli, P. Scharff-Hansen, A. D. Schaile, H. J. Burckhart, Jacqueline Batley, C. Beeston, M. J. Oreglia, W. M. Sang, Gregor Herten, B. Wilkens, A. Biguzzi, Raimund Ströhmer, N. Rodning, P. M. Watkins, A. Rooke, J. E. Pilcher, Gabriella Pasztor, Claudio Grandi, J. Grunhaus, D. C. Imrie, P. R. Hobson, J. G. Layter, I. Nakamura, A. K. Honma, R. Van Kooten, F. G. Oakham, D. Eatough, B. Schmitt, E. L. Barberio, R. Bartoldus, D. Lui, B. Nellen, A. M. Smith, A. Oh, Paolo Capiluppi, J-P. Meyer, John Allison, Richard Keeler, R. J. Hemingway, H. O. Ogren, L. Levinson, G. D. Long, M. Schumacher, K. Stephens, G. A. Snow, C. P. Ward, E. Lefebvre, R. L. Coxe, Christoph Geich-Gimbel, J. R. Carter, Georges Azuelos, C. R. Jones, G. Mikenberg, T. Kawamoto, Stefan Schmitt, A. Macpherson, B. W. Kennedy, P. Jovanovic, R. Lahmann, Austin Ball, S. Söldner-Rembold, F. Odorici, A. Hocker, G. N. Patrick, Peter Krieger, R. G. Kellogg, P. E.L. Clarke, Alessandro Montanari, R. Davis, Silvia Arcelli, Hans-Christian Schultz-Coulon, Csaba Hajdu, D. Chrisman, R. Perez-Ochoa, G. D. Lafferty, M. Verzocchi, K. W. Bell, Otmar Biebel, H. G. Evans, M. J. Goodrick, P. Igo-Kemenes, N. I. Geddes, Michael Hildreth, P. Gagnon, M. K. Jones, J. P. Martin, J. Letts, Christoph Rembser, E. Tsur, S. Komamiya, V. Gibson, J. S. White, Stefano Marcellini, C. Hartmann, D. G. Fong, J. Gascon, D. E. Plane, S. Dado, J. Pinfold, J. C. Hill, D. Lazic, T. J. McMahon, C. Couyoumtzelis, P. Mättig, S. Asai, Vakhtang Kartvelishvili, G. P. Siroli, S. De Jong, Christoph Schwick, K. Ackerstaff, F. Fiedler, F. Wäckerle, L. Brigliadori, S. Baumann, H. Jeremie, Stephen Lloyd, Stephen Hillier, R. K. Carnegie, E. Gross, Dave Charlton, B. Poli, F. Scharf, German Martinez, I. J. Bloodworth, Peter Schleper, K. Kawagoe, J. E. Conboy, A. Fürtjes, K. Sachs, J. Goldberg, E. A. Mckigney, S. Tarem, B. C. Shen, G. M. Dallavalle, T. R. Junk, J. M. Roney, M. Fierro, J. E.G. Edwards, R. Bürgin, H. M. Fischer, A. N. Bell, D. M. Gingrich, M. Herndon, B. Dienes, I. Trigger, A. Joly, J. W. Gary, W. P. Lai, D. S. Koetke, Marcello Mannelli, Guenter Duckeck, Lutz Feld, R. Mir, M. Bobinski, Norbert Wermes, Sherry Towers, Paolo Giacomelli, J. A. Wilson, M. Hansroul, D. R. Ward, M. Jimack, Siegfried Bethke, T. Kress, W. G. Scott, A. Michelini, H. Mes, O. Schaile, P. W. Jeffreys, M. Foucher, I. P. Duerdoth, S. D. Bird, G. G. Hanson, A. M. Lee, G. Alexander, M. Boutemeur, F. S. Merritt, Richard Teuscher, S. Braibant, S. Yamashita, R. Rylko, B. Stockhausen, Paul Kyberd, F. K. Loebinger, D. I. Futyan, A. S. Turcot, C. Burgard, I. Cohen, Ivor Fleck, G. Giacomelli, S. W. O'Neale, A. Jawahery, Joleen Pater, M. F. Turner-Watson, R. W. Springer, R. J. Homer, D. Karlen, T. Saeki, P. I. Kayal, S. F. Ashby, R. Giacomelli, Sven Menke, Daniele Bonacorsi, Z. Trácsanyi, Peter Sherwood, S. Mihara, S. M. Gascon-Shotkin, M. A. Thomson, S. Robertson, D. Glenzinski, Dezso Horvath, M. J. Losty, R. Sobie, M. S. Dixit, Frans Meijers, P. S. Wells, J. Bechtluft, K. J. Anderson, M. Fanti, D. Zer-Zion, V. Blobel, J. A. McKenna, J. Ludwig, Reda Tafirout, Klaus Kurt Desch, S. A. Robins, R. Hawkings, K. Runge, P. Bock, E. Torrence, S. Petzold, Matthew Evans, A. M. Rossi, M. Kolrep, M. Sproston, Terry Richard Wyatt, C. Y. Chang, P. Vikas, D. Lanske, T. Mori, J. von Krogh, D. Lellouch, W. R. Gibson, J. E. Bloomer, D. Axen, K. R. Hossain, S. B. Anderson, J. Pálinkás, J. Kirk, P. Szymanski, P. Taras, Michael Kobel, R. M. Brown, E. von Tärne, Theodoros Geralis, A. Skillman, O. C. Cooke, P. Pfeifenschneider, A. T. Watson, L. A. del Pozo, Stan Bentvelsen, Allen Mincer, T. P. Kokott, T. Mashimo, Alessandra Fanfani, J. Patt, André Schöning, Robert McPherson, C. Sbarra, P. Huntemeyer, A. A. Carter, Ron Folman, T. Kobayashi, Mathieu Doucet, R. D. Heuer, P. Utzat, A. A. Faust, Fabrizio Fabbri, J. Schieck, D. M. Strom, E. Duchovni, W. Mohr, A. Posthaus, K. Nagai, D. R. Rust, J. Kanzaki, S. Tanaka, Tara Shears, P. A. Hart, P. Poffenberger, K. Ishii, Claire Shepherd-Themistocleous, A. Wagner, Matthias Schröder, T. Behnke, J. Steuerer, M. Thiergen, A. Macchiolo, M. Gruwé, C. M. Hawkes, Richard Nisius, Marco Cuffiani, U. Müller, A. J. Martin, C. K. Hargrove, K. Stoll, Andris Skuja, and Y. Rozen
Subjects: Physics, Particle physics, Missing energy, Physics and Astronomy (miscellaneous), Electron–positron annihilation, Physics beyond the Standard Model, Standard Model, Nuclear physics, Pair production, Neutralino, High Energy Physics::Experiment, Production (computer science), Engineering (miscellaneous), Energy (signal processing)
Abstract: Photonic events with large missing energy have been observed in $\mathrm{e^+e^-}$ collisions at centre-of-mass energies of 130, 136, 161 and 172 GeV using the OPAL detector at LEP. Results are presented based on search topologies designed to select events with a single photon and missing transverse energy or events with a pair of acoplanar photons. In both search topologies, cross-section measurements are performed within the kinematic acceptance of the selection. These results are compared with the expectations from the Standard Model processes ${\rm e^+e^-}\to \nu\overline\nu \gamma (\gamma )$ (single-photon) and ${\rm e^+e^-}\to \nu\overline\nu \gamma \gamma (\gamma )$ (acoplanar-photons). No evidence is observed for new physics contributions to these final states. Upper limits on $\sigma({\rm e^+e^- \to XY)\cdot BR(X\to Y\gamma })$ and $\sigma({\rm e^+e^- \to XX)\cdot BR^2(X\to Y\gamma })$ are derived for the case of stable and invisible Y. These limits apply to single and pair production of excited neutrinos (${\rm X}= \nu^*,{\rm Y}= \nu$), to neutralino production (${\rm X}=\tilde\chi^0_2, {\rm Y}=\tilde\chi^0_1$), and to supersymmetric models in which ${\rm X}= \tilde\chi^0_1$ and ${\rm Y}=\tilde{\rm G}$ is a light gravitino. For the latter scenario, the results of the acoplanar-photons search are used to provide mode l-dependent lower limits on the mass of the lightest neutralino.
Published: 1998
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22. Measurements of the Bs0 and Λb0 lifetimes

Author: K Ackerstaff, G Alexander, J Allison, N Altekamp, K.J Anderson, S Anderson, S Arcelli, S Asai, S.F Ashby, D Axen, G Azuelos, A.H Ball, E Barberio, R.J Barlow, R Bartoldus, J.R Batley, S Baumann, J Bechtluft, C Beeston, T Behnke, A.N Bell, K.W Bell, G Bella, S Bentvelsen, S Bethke, S Betts, O Biebel, A Biguzzi, S.D Bird, V Blobel, I.J Bloodworth, J.E Bloomer, M Bobinski, P Bock, D Bonacorsi, M Boutemeur, S Braibant, L Brigliadori, R.M Brown, H.J Burckhart, C Burgard, R Bürgin, P Capiluppi, R.K Carnegie, A.A Carter, J.R Carter, C.Y Chang, D.G Charlton, D Chrisman, P.E.L Clarke, I Cohen, J.E Conboy, O.C Cooke, C Couyoumtzelis, R.L Coxe, M Cuffiani, S Dado, C Dallapiccola, G.M Dallavalle, R Davis, S De Jong, L.A del Pozo, K Desch, B Dienes, M.S Dixit, M Doucet, E Duchovni, G Duckeck, I.P Duerdoth, D Eatough, J.E.G Edwards, P.G Estabrooks, H.G Evans, M Evans, F Fabbri, A Fanfani, M Fanti, A.A Faust, L Feld, F Fiedler, M Fierro, H.M Fischer, I Fleck, R Folman, D.G Fong, M Foucher, A Fürtjes, D.I Futyan, P Gagnon, J.W Gary, J Gascon, S.M Gascon-Shotkin, N.I Geddes, C Geich-Gimbel, T Geralis, G Giacomelli, P Giacomelli, R Giacomelli, V Gibson, W.R Gibson, D.M Gingrich, D Glenzinski, J Goldberg, M.J Goodrick, W Gorn, C Grandi, E Gross, J Grunhaus, M Gruwé, C Hajdu, G.G Hanson, M Hansroul, M Hapke, C.K Hargrove, P.A Hart, C Hartmann, M Hauschild, C.M Hawkes, R Hawkings, R.J Hemingway, M Herndon, G Herten, R.D Heuer, M.D Hildreth, J.C Hill, S.J Hillier, P.R Hobson, A Hocker, R.J Homer, A.K Honma, D Horváth, K.R Hossain, R Howard, P Hüntemeyer, D.E Hutchcroft, P Igo-Kemenes, D.C Imrie, M.R Ingram, K Ishii, A Jawahery, P.W Jeffreys, H Jeremie, M Jimack, A Joly, C.R Jones, G Jones, M Jones, U Jost, P Jovanovic, T.R Junk, J Kanzaki, D Karlen, V Kartvelishvili, K Kawagoe, T Kawamoto, P.I Kayal, R.K Keeler, R.G Kellogg, B.W Kennedy, J Kirk, A Klier, S Kluth, T Kobayashi, M Kobel, D.S Koetke, T.P Kokott, M Kolrep, S Komamiya, T Kress, P Krieger, J von Krogh, P Kyberd, G.D Lafferty, R Lahmann, W.P Lai, D Lanske, J Lauber, S.R Lautenschlager, J.G Layter, D Lazic, A.M Lee, E Lefebvre, D Lellouch, J Letts, L Levinson, S.L Lloyd, F.K Loebinger, G.D Long, M.J Losty, J Ludwig, D Lui, A Macchiolo, A Macpherson, M Mannelli, S Marcellini, C Markopoulos, C Markus, A.J Martin, J.P Martin, G Martinez, T Mashimo, P Mättig, W.J McDonald, J McKenna, E.A Mckigney, T.J McMahon, R.A McPherson, F Meijers, S Menke, F.S Merritt, H Mes, J Meyer, A Michelini, G Mikenberg, D.J Miller, A Mincer, R Mir, W Mohr, A Montanari, T Mori, U Müller, S Mihara, K Nagai, I Nakamura, H.A Neal, B Nellen, R Nisius, S.W O'Neale, F.G Oakham, F Odorici, H.O Ogren, A Oh, N.J Oldershaw, M.J Oreglia, S Orito, J Pálinkás, G Pásztor, J.R Pater, G.N Patrick, J Patt, R Perez-Ochoa, S Petzold, P Pfeifenschneider, J.E Pilcher, J Pinfold, D.E Plane, P Poffenberger, B Poli, A Posthaus, C Rembser, S Robertson, S.A Robins, N Rodning, J.M Roney, A Rooke, A.M Rossi, P Routenburg, Y Rozen, K Runge, O Runolfsson, U Ruppel, D.R Rust, R Rylko, K Sachs, T Saeki, W.M Sang, E.K.G Sarkisyan, C Sbarra, A.D Schaile, O Schaile, F Scharf, P Scharff-Hansen, J Schieck, P Schleper, B Schmitt, S Schmitt, A Schöning, M Schröder, H.C Schultz-Coulon, M Schumacher, C Schwick, W.G Scott, T.G Shears, B.C Shen, C.H Shepherd-Themistocleous, P Sherwood, G.P Siroli, A Sittler, A Skillman, A Skuja, A.M Smith, G.A Snow, R Sobie, S Söldner-Rembold, R.W Springer, M Sproston, K Stephens, J Steuerer, B Stockhausen, K Stoll, D Strom, R Ströhmer, P Szymanski, R Tafirout, S.D Talbot, S Tanaka, P Taras, S Tarem, R Teuscher, M Thiergen, M.A Thomson, E von Törne, E Torrence, S Towers, I Trigger, Z Trócsányi, E Tsur, A.S Turcot, M.F Turner-Watson, P Utzat, R Van Kooten, M Verzocchi, P Vikas, E.H Vokurka, H Voss, F Wäckerle, A Wagner, C.P Ward, D.R Ward, P.M Watkins, A.T Watson, N.K Watson, P.S Wells, N Wermes, J.S White, B Wilkens, G.W Wilson, J.A Wilson, T.R Wyatt, S Yamashita, G Yekutieli, V Zacek, and D Zer-Zion
Subjects: Baryon, Physics, Nuclear and High Energy Physics, Particle physics, Meson, 010308 nuclear & particles physics, 0103 physical sciences, Hadron, High Energy Physics::Experiment, 010306 general physics, Lambda, 01 natural sciences, Bar (unit)
Abstract: This paper presents updated measurements of the lifetimes of the B^0_s meson and the \Lambda_b baryon using 4.4 million hadronic Z^0 decays recorded by the OPAL detector at LEP from 1990 to 1995. A sample of B^0_s decays is obtained using D_s^- \ell^+ combinations, where the D_s^- is fully reconstructed in the \phi \pi^-, K^*0 K^- and K^- K^0_S decay channels and partially reconstructed in the \phi \ell^- \nu(bar) X decay mode. A sample of \Lambda_b decays is obtained using \Lambda_c^+ \ell^- combinations, where the \Lambda_c^+ is fully reconstructed in its decay to a p K^- \pi^+ final state and partially reconstructed in the \Lambda \ell^+ \nu X decay channel. From 172 +/- 28 D_s^- \ell^+ combinations attributed to B^0_s decays, the measured lifetime is \tau(B^0_s) = 1.50 +0.16 -0.15 +/- 0.04 ps, where the errors are statistical and systematic, respectively. From the 129 +\- 25 \Lamda_c^+ \ell^- combinations attributed to \Lambda_b decays, the measured lifetime \tau(\Lambda_b) = 1.29 +0.24 -0.22 +/- 0.06 ps, where the errors are statistical and systematic, respectively.
Published: 1998
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23. Multi-photon final states in e+e− collisions at ∝s =130-172 GeV

Author: S. Petzold, G. D. Long, Tetsuro Mashimo, J. M. Roney, Anna Macchiolo, W. Gorn, Gabriella Pasztor, S. D. Bird, P. E. L. Clarke, W. Mohr, A. Posthaus, Matthias Schröder, G. A. Snow, S. R. Lautenschlager, H. A. Neal, M. Jimack, C. P. Ward, John Allison, B. Schmitt, K. Nagai, Eduardo Ros, N. K. Watson, S. M. Gascon-Shotkin, M. Thiergen, D. L. Rees, S. Söldner-Rembold, Kiyotomo Kawagoe, S. J. De Jong, Satoshi Mihara, Daniel Lellouch, Hildreth, P. Scharff-Hansen, C.J. Beeston, A. P. Wagner, Frank Fiedler, D. Axen, S. Komamiya, A. Jawahery, David G. Charlton, Gideon Bella, BT Bouwens, Rick J. Van Kooten, Eugene P. Gross, F. Wäckerle, Paolo Giacomelli, Takehiko Mori, H. J. Burckhart, Jacqueline Batley, M. Hansroul, Georges Azuelos, E. Tsur, C. M. Hawkes, S. H. Robertson, J. Goldberg, B. Nellen, N. J. Oldershaw, E. Lefebvre, J. Steuerer, A. M. Rossi, Isabel Marian Trigger, K. W. Bell, F. Scharf, German Martinez, Gideon Alexander, Otmar Biebel, Marco Verzocchi, R. Bartoldus, J. W. Gary, J. Palinkas, K. Sachs, F. Odorici, R. G. Kellogg, C. H. Shepherd-Themistocleous, R. J. Homer, D. S. Koetke, Csaba Hajdu, Stefano Marcellini, James Letts, A. D. Schaile, A. S. Turcot, P. Igo-Kemenes, Gy. Wolf, Shigenori Tanaka, Shlomo Dado, K. Ishii, K. R. Hossain, Paolo Capiluppi, P.A. Hart, H. Jeremie, H. O. Ogren, J. C. Hill, R. J. Teuscher, A. M. Smith, A. Michelini, V. Kartvelishvili, S. A. Robins, D. Rigby, R. J. Hemingway, Christoph Geich-Gimbel, D. R. Rust, J. Ludwig, B. C. Shen, K. Runge, P. Bock, J. R. Carter, P. I. Kayal, T. Behnke, Siegfried Bethke, G. Duckeck, W. G. Scott, P. G. Estabrooks, V. Gibson, H. G. Evans, P. Szymanski, M. J. Goodrick, Doug Gingrich, J. A. McKenna, I. Cohen, P. Jovanovic, I. J. Bloodworth, James Pinfold, I. Nakamura, R. Perez-Ochoa, E. do Couto e Silva, Ehud Duchovni, E. von Törne, C. R. Jones, Richard Nisius, U. Müller, T. Kress, Peter Krieger, D. G. Fong, Carla Sbarra, J. Gascon, P. Gagnon, Dezso Horvath, M. J. Losty, Sven Menke, Alessandro Montanari, A. J. Martin, K. Ackerstaff, P. M. Watkins, Takayuki Saeki, Jean-Arcady Meyer, Sherry Towers, T. Kawamoto, Marco Cuffiani, N. L. Rodning, A. Skillman, D. E. Hutchcroft, C. Dallapiccola, M. Kolrep, D. Karlen, Carsten Daniel Burgard, B. Poli, G. Mikenberg, O. Schaile, I. P. Duerdoth, Yoram Rozen, V. Zacek, A. Sittler, S. Orito, A. K. Honma, N. Altekamp, M. Foucher, Claudio Grandi, Peter Schleper, C. K. Hargrove, Zoltan Laszlo Trocsanyi, S. J. Hillier, Tara Shears, Robert McPherson, B. Stockhausen, P. Kyberd, P. Hüntemeyer, S. B. Anderson, F. K. Loebinger, D. J. Miller, A. H. Ball, Silvia Arcelli, M. F. Turner-Watson, Meirin Oan Evans, D. C. Imrie, Mathieu Doucet, M. Hapke, R. Bürgin, Marcello Mannelli, D. M. Strom, Matthew Herndon, Fabrizio Fabbri, M. Morii, Markus Schumacher, E.K.G. Sarkisian, H. Voss, G. W. Wilson, Peter R Hobson, Ivor Fleck, G. P. Siroli, S. Baumann, M. J. Pearce, U. Jost, R. Mir, Stan Bentvelsen, Christoph Schwick, J.A. Lauber, M. J. Oreglia, H. Mes, D Chrisman, E. A. Mckigney, S. Braibant, J. E. Conboy, S. D. Talbot, M. Sproston, Joleen Pater, Peter Sherwood, D. Zer-Zion, W. P. Lai, A. Fürtjes, Stefan Kluth, T. Geralis, R. D. Heuer, Shlomit Tarem, F. G. Oakham, Stefan Schmitt, Norbert Wermes, G. N. Patrick, E. L. Barberio, A. Klier, D. Eatough, R. Giacomelli, G. D. Lafferty, D. I. Futyan, Volker Blobel, P. Routenburg, T. R. Wyatt, Jochen Schieck, T. R. Junk, M. Gruwe, Hans-Christian Schultz-Coulon, Thomson, M. J. Kobel, P. Mättig, Shoji Asai, Stephen Lloyd, A. A. Faust, D. Glenzinski, Satoru Yamashita, Robert M Brown, Gregor Herten, R. Rylko, Robert Wayne Springer, M. Boutemeur, M. Fierro, J. E.G. Edwards, F. S. Merritt, T. P. Kokott, Dixit, P. W. Jeffreys, P. S. Wells, David E. Plane, B. Wilkens, J. E. Bloomer, T. Kobayashi, A. M. Lee, A. Macpherson, Richard Keeler, P. Vikas, R. J. Sobie, Robert Lahmann, R. Howard, J. S. White, Alexander Oh, J. E. Pilcher, D. Lanske, J. Bechtluft, M. Hauschild, C. Markus, G. T. Jones, E. H. Vokurka, P R Poffenberger, J. Grunhaus, C. Hartmann, H. Fischer, O. Runolfsson, Alan Watson, Matthew Jones, Reda Tafirout, Klaus Kurt Desch, W. R. Gibson, A. Joly, Lorne Levinson, B. W. Kennedy, N. I. Geddes, Roger Barlow, K. Stephens, W.John McDonald, D. Lazic, D. R. Ward, U. Ruppel, M. R. Ingram, C. Y. Chang, P. Taras, G. Yekutieli, Allen Mincer, Marcello Fanti, Julie Kirk, P. Pfeifenschneider, A. A. Carter, Ron Folman, J. Patt, André Schöning, G. G. Hanson, G.Marco Dallavalle, P. Utzat, Beatrix Dienes, L. Brigliadori, G. Giacomelli, Daniele Bonacorsi, O. C. Cooke, S. W. O'Neale, R. Davies, P. Schenk, K. J. Anderson, J. von Krogh, Frans Meijers, R. J. Hawkings, L. A. del Pozo, A. Biguzzi, A. Rooke, J. G. Layter, T. J. McMahon, R. K. Carnegie, M. Bobinski, J. A. Wilson, J.P. Martin, A. N. Bell, K. Stoll, and Andris Skuja
Subjects: Nuclear physics, Physics, Particle physics, Angular distribution, Physics and Astronomy (miscellaneous), Electron–positron annihilation, Engineering (miscellaneous)
Published: 1998
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24. Polarization and forward-backward asymmetry of $\Lambda$ baryons in hadronic Z $^0$ decays

Author: Ackerstaff, K, Alexander, G, Allison, J, Altekamp, N, Anderson, KJ, Anderson, S, Arcelli, S, Asai, S, Axen, D, Azuelos, G, Ball, AH, Gorn, W, Grandi, C, Gross, E, Grunhaus, J, Gruwe, M, Hajdu, C, Hanson, GG, Hansroul, M, Hapke, M, Hargrove, CK, Barberio, E, Hart, PA, Hartmann, C, Hauschild, M, Hawkes, CM, Hawkins, R, Hemingway, RJ, Herndon, M, Herten, G, Heuer, RD, Hildreth, MD, Barlow, RJ, Hill, JC, Hillier, SJ, Hobson, PR, Homer, RJ, Honma, AK, Horvath, D, Hossain, KR, Howard, R, Huntemeyer, P, Hutchcroft, DE, Bartoldus, R, Igo-Kemenes, P, Imrie, DC, Ingram, MR, Ishii, K, Jawahery, A, Jeffreys, PW, Jeremie, H, Jimack, M, Joly, A, Jones, CR, Batley, JR, Jones, G, Jones, M, Jost, U, Jovanovic, P, Junk, TR, Karlen, D, Kartvelishvili, V, Kawagoe, K, Kawamoto, T, Kayal, PI, Baumann, S, Keeler, RK, Kellogg, RG, Kennedy, BW, Kirk, J, Klier, A, Kluth, S, Kobayashi, T, Kobel, M, Koetke, DS, Kokott, TP, Bechtluft, J, Kolrep, M, Komamiya, S, Kress, T, Krieger, P, von Krogh, J, Kyberd, P, Lafferty, GD, Lahmann, R, Lai, WP, Lamarche, F, Beeston, C, Lanske, D, Lauber, J, Lautenschlager, SR, Layter, JG, Lazic, D, Lee, AM, Lefebvre, E, Lellouch, D, Letts, J, Levinson, L, Behnke, T, Lloyd, SL, Loebinger, FK, Long, GD, Losty, MJ, Ludwig, J, Macchiolo, A, Macpherson, A, Mannelli, M, Marcellini, S, Markus, C, Bell, AN, Martin, AJ, Martin, JP, Martinez, G, Mashimo, T, Mattig, P, McDonald, WJ, McKenna, J, Mckigney, EA, McMahon, TJ, McPherson, RA, Bell, KW, Meijers, F, Menke, S, Merritt, FS, Mes, H, Meyer, J, Michelini, A, Mikenberg, G, Miller, DJ, Mincer, A, Mir, R, Bella, G, Mohr, W, Montanari, A, Mori, T, Morii, M, Muller, U, Mihara, S, Nagai, K, Nakamura, I, Neal, HA, Nellen, B, Bentvelsen, S, Nisius, R, O'Neale, SW, Oakham, FG, Odorici, F, Ogren, HO, Oh, A, Oldershaw, NJ, Oreglia, MJ, Orito, S, Palinkas, J, Bethke, S, Pasztor, G, Pater, JR, Patrick, GN, Patt, J, Pearce, MJ, Perez-Ochoa, R, Petzold, S, Pfeifenschneider, P, Pilcher, JE, Pinfold, J, Biebel, O, Plane, DE, Poffenberger, P, Poli, B, Posthaus, A, Rees, DL, Rigby, D, Robertson, S, Robins, SA, Rodning, N, Roney, JM, Biguzzi, A, Rooke, A, Ros, E, Rossi, AM, Routenburg, P, Rozen, Y, Runge, K, Runolfsson, O, Ruppel, U, Rust, DR, Rylko, R, Bird, SD, Sachs, K, Saeki, T, Sarkisyan, EKG, Sbarra, C, Schaile, AD, Schaile, O, Scharf, F, Scharff-Hansen, P, Schenk, P, Schieck, J, Blobel, V, Schleper, P, Schmitt, B, Schmitt, S, Schoning, A, Schroder, M, Schultz-Coulon, HC, Schumacher, M, Schwick, C, Scott, WG, Shears, TG, Bloodworth, IJ, Shen, BC, Shepherd-Themistocleous, CH, Sherwood, P, Siroli, GP, Sittler, A, Skillman, A, Skuja, A, Smith, AM, Snow, GA, Sobie, R, Bloomer, JE, Soldner-Rembold, S, Springer, RW, Sproston, M, Stephens, K, Steuerer, J, Stockhausen, B, Stoll, K, Strom, D, Szymanski, P, Tafirout, R, Bobinski, M, Talbot, SD, Tanaka, S, Taras, P, Tarem, S, Teuscher, R, Thiergen, M, Thomson, MA, von Torne, E, Towers, S, Trigger, I, Bock, P, Trocsanyi, Z, Tsur, E, Turcot, AS, Turner-Watson, MF, Utzat, P, Van Kooten, R, VanDenPlas, D, Verzocchi, M, Vikas, P, Vokurka, EH, Bonacorsi, D, Voss, H, Wackerle, F, Wagner, A, Ward, CP, Ward, DR, Watkins, PM, Watson, AT, Watson, NK, Wells, PS, Wermes, N, Boutemeur, M, White, JS, Wilkems, B, Wilson, GW, Wilson, JA, Wolf, G, Wyatt, TR, Yamashita, S, Yekutieli, G, Zacek, W, Zer-Zion, D, Bouwens, BT, OPAL Collaboration, Braibant, S, Brigliadori, L, Brown, RM, Burckhart, HJ, Burgard, C, Burgin, R, Capiluppi, P, Carnegie, RK, Carter, AA, Carter, JR, Chang, CY, Charlton, DG, Chrisman, D, Clarke, PEL, Cohen, I, Conboy, JE, Cooke, OC, Cuffani, M, Dado, S, Dallapiccola, C, Dallavalle, GM, Davis, R, De Jong, S, del Pozo, LA, Desch, K, Dienes, B, Dixit, MS, Silva, EDE, Doucet, M, Duchovni, E, Duckeck, G, Duerdoth, IP, Eatough, D, Edwards, JEG, Estabrooks, PG, Evans, HG, Evans, M, Fabbri, F, Fanti, M, Faust, AA, Fiedler, F, Fierro, M, Fischer, HM, Fleck, I, Folman, R, Fong, DG, Foucher, M, Furtjes, A, Futyan, DI, Gagnon, P, Gary, JW, Gascon, J, Gascon-Shotkin, SM, Geddes, NI, Geich-Gimbel, C, Geralis, T, Giacomelli, G, Giacomelli, P, Giacomelli, R, Gibson, V, Gibson, WR, Gingrich, DM, Glenzinski, D, Goldberg, J, and Goodrick, MJ
Subjects: Particle physics, Physics and Astronomy (miscellaneous), LUND MONTE-CARLO, media_common.quotation_subject, Hadron, Lambda baryon, Lambda, 01 natural sciences, Asymmetry, High momentum, JET FRAGMENTATION, 0103 physical sciences, Nuclear Experiment, 010306 general physics, DETECTOR, Engineering (miscellaneous), media_common, Physics, E+E-PHYSICS, 010308 nuclear & particles physics, LEP, Polarization (waves), Hadronization, Transverse plane, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: The longitudinal polarization, the transverse polarization, and the forward-backward asymmetry of Lambda baryons have been measured using a sample of 4.34 million hadronic Z^0 decays collected with the OPAL detector at LEP between 1990 and 1995. These results are important as an aid to the understanding of hadronization mechanisms. Significant longitudinal polarization has been observed at intermediate and high momentum. For x_E = 2 E_{Lambda}/\sqrt{s}) > 0.3, the longitudinal polarization has been measured to be -32.9 +/- 5.5(stat) +/- 5.2(syst)%. We have observed no transverse polarization. A significant forward-backward asymmetry has been measured and can be described by a JETSET model. The longitudinal polarization, the transverse polarization, and the forward-backward asymmetry of Lambda baryons have been measured using a sample of 4.34 million hadronic Z^0 decays collected with the OPAL detector at LEP between 1990 and 1995. These results are important as an aid to the understanding of hadronization mechanisms. Significant longitudinal polarization has been observed at intermediate and high momentum. For x_E = 2 E_{Lambda}/\sqrt{s}) > 0.3, the longitudinal polarization has been measured to be -32.9 +/- 5.5(stat) +/- 5.2(syst)%. We have observed no transverse polarization. A significant forward-backward asymmetry has been measured and can be described by a JETSET model.
Published: 1998
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25. Search for the Bc meson in hadronic Z0 decays

Author: K Ackerstaff, G Alexander, J Allison, N Altekamp, K.J Anderson, S Anderson, S Arcelli, S Asai, S.F Ashby, D Axen, G Azuelos, A.H Ball, E Barberio, R.J Barlow, R Bartoldus, J.R Batley, S Baumann, J Bechtluft, C Beeston, T Behnke, A.N Bell, K.W Bell, G Bella, S Bentvelsen, S Bethke, S Betts, O Biebel, A Biguzzi, S.D Bird, V Blobel, I.J Bloodworth, J.E Bloomer, M Bobinski, P Bock, D Bonacorsi, M Boutemeur, S Braibant, L Brigliadori, R.M Brown, H.J Burckhart, C Burgard, R Bürgin, P Capiluppi, R.K Carnegie, A.A Carter, J.R Carter, C.Y Chang, D.G Charlton, D Chrisman, P.E.L Clarke, I Cohen, J.E Conboy, O.C Cooke, C Couyoumtzelis, R.L Coxe, M Cuffiani, S Dado, C Dallapiccola, G.M Dallavalle, R Davis, S De Jong, L.A del Pozo, K Desch, B Dienes, M.S Dixit, M Doucet, E Duchovni, G Duckeck, I.P Duerdoth, D Eatough, J.E.G Edwards, P.G Estabrooks, H.G Evans, M Evans, F Fabbri, A Fanfani, M Fanti, A.A Faust, L Feld, F Fiedler, M Fierro, H.M Fischer, I Fleck, R Folman, D.G Fong, M Foucher, A Fürtjes, D.I Futyan, P Gagnon, J.W Gary, J Gascon, S.M Gascon-Shotkin, N.I Geddes, C Geich-Gimbel, T Geralis, G Giacomelli, P Giacomelli, R Giacomelli, V Gibson, W.R Gibson, D.M Gingrich, D Glenzinski, J Goldberg, M.J Goodrick, W Gorn, C Grandi, E Gross, J Grunhaus, M Gruwé, C Hajdu, G.G Hanson, M Hansroul, M Hapke, C.K Hargrove, P.A Hart, C Hartmann, M Hauschild, C.M Hawkes, R Hawkings, R.J Hemingway, M Herndon, G Herten, R.D Heuer, M.D Hildreth, J.C Hill, S.J Hillier, P.R Hobson, A Hocker, R.J Homer, A.K Honma, D Horváth, K.R Hossain, R Howard, P Hüntemeyer, D.E Hutchcroft, P Igo-Kemenes, D.C Imrie, M.R Ingram, K Ishii, A Jawahery, P.W Jeffreys, H Jeremie, M Jimack, A Joly, C.R Jones, G Jones, M Jones, U Jost, P Jovanovic, T.R Junk, J Kanzaki, D Karlen, V Kartvelishvili, K Kawagoe, T Kawamoto, P.I Kayal, R.K Keeler, R.G Kellogg, B.W Kennedy, J Kirk, A Klier, S Kluth, T Kobayashi, M Kobel, D.S Koetke, T.P Kokott, M Kolrep, S Komamiya, T Kress, P Krieger, J von Krogh, P Kyberd, G.D Lafferty, R Lahmann, W.P Lai, D Lanske, J Lauber, S.R Lautenschlager, J.G Layter, D Lazic, A.M Lee, E Lefebvre, D Lellouch, J Letts, L Levinson, S.L Lloyd, F.K Loebinger, G.D Long, M.J Losty, J Ludwig, D Lui, A Macchiolo, A Macpherson, M Mannelli, S Marcellini, C Markopoulos, C Markus, A.J Martin, J.P Martin, G Martinez, T Mashimo, P Mättig, W.J McDonald, J McKenna, E.A Mckigney, T.J McMahon, R.A McPherson, F Meijers, S Menke, F.S Merritt, H Mes, J Meyer, A Michelini, G Mikenberg, D.J Miller, A Mincer, R Mir, W Mohr, A Montanari, T Mori, U Müller, S Mihara, K Nagai, I Nakamura, H.A Neal, B Nellen, R Nisius, S.W O'Neale, F.G Oakham, F Odorici, H.O Ogren, A Oh, N.J Oldershaw, M.J Oreglia, S Orito, J Pálinkás, G Pásztor, J.R Pater, G.N Patrick, J Patt, R Perez-Ochoa, S Petzold, P Pfeifenschneider, J.E Pilcher, J Pinfold, D.E Plane, P Poffenberger, B Poli, A Posthaus, C Rembser, S Robertson, S.A Robins, N Rodning, J.M Roney, A Rooke, A.M Rossi, P Routenburg, Y Rozen, K Runge, O Runolfsson, U Ruppel, D.R Rust, R Rylko, K Sachs, T Saeki, W.M Sang, E.K.G Sarkisyan, C Sbarra, A.D Schaile, O Schaile, F Scharf, P Scharff-Hansen, J Schieck, P Schleper, B Schmitt, S Schmitt, A Schöning, M Schröder, H.C Schultz-Coulon, M Schumacher, C Schwick, W.G Scott, T.G Shears, B.C Shen, C.H Shepherd-Themistocleous, P Sherwood, G.P Siroli, A Sittler, A Skillman, A Skuja, A.M Smith, G.A Snow, R Sobie, S Söldner-Rembold, R.W Springer, M Sproston, K Stephens, J Steuerer, B Stockhausen, K Stoll, D Strom, R Ströhmer, P Szymanski, R Tafirout, S.D Talbot, S Tanaka, P Taras, S Tarem, R Teuscher, M Thiergen, M.A Thomson, E von Törne, E Torrence, S Towers, I Trigger, Z Trócsányi, E Tsur, A.S Turcot, M.F Turner-Watson, P Utzat, R Van Kooten, M Verzocchi, P Vikas, E.H Vokurka, H Voss, F Wäckerle, A Wagner, C.P Ward, D.R Ward, P.M Watkins, A.T Watson, N.K Watson, P.S Wells, N Wermes, J.S White, B Wilkens, G.W Wilson, J.A Wilson, T.R Wyatt, S Yamashita, G Yekutieli, V Zacek, and D Zer-Zion
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Muon, Meson, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Hadron, FOS: Physical sciences, Electron, 01 natural sciences, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Particle Physics - Experiment
Abstract: A search for decays of the B_c meson was performed using data collected from 1990-1995 with the OPAL detector on or near the Z peak at LEP. The decay channels B_c^+ -> J/psi pi^+, B_c^+ -> J/psi a_1^+ and B_c^+ -> J/psi ell^+ nu were investigated, where ell denotes an electron or a muon. Two candidates are observed in the mode B_c^+ -> J/psi pi^+, with an estimated background of (0.63 +/- 0.20) events. The weighted mean of the masses of the two candidates is (6.32 +/- 0.06) GeV/c^2, which is consistent with the predicted mass of the B_c meson. One candidate event is observed in the mode B_c^+ -> J/psi ell^+ nu with an estimated background of (0.82 +/- 0.19) events. No candidate events are observed in the B_c^+ -> J/psi a_1^+ decay mode, with an estimated background of (1.10 +/- 0.22) events. Upper bounds at the 90% confidence level are set on the production rates for these processes., 18 pages, LaTeX, uses a4p.sty, 6 eps figures included, submitted to Phys. Lett. B
Published: 1998
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26. Production of P-wave charm and charm-strange mesons in hadronic Z $^0$ decays

Author: Matthias Schröder, D. L. Rees, M. A. Thomson, E. K. U. Gross, M. Sproston, F. Scharf, G. G. Hanson, German Martinez, M. Thiergen, Hans-Christian Schultz-Coulon, Randall Sobie, G. Giacomelli, J. Letts, Michael Schulz, G. D. Lafferty, H. M. Fischer, J. Schieck, W. Mohr, Ekg Sarkisyan, M. Fanti, A. Posthaus, J. Lauber, L. Brigliadori, K. Stoll, Gideon Bella, R. W. Springer, H. Mes, I. P. Duerdoth, Otmar Biebel, H. J. Burckhart, J. Grunhaus, P. W. Jeffreys, K. Sachs, Shlomo Dado, Andris Skuja, Jacqueline Batley, J. Goldberg, B. Nellen, S. Petzold, Tetsuro Mashimo, Tara Shears, P. A. Hart, Daniel Lellouch, Robert McPherson, Takehiko Mori, Mathieu Doucet, Guenter Duckeck, P. G. Estabrooks, D. Chrisman, G. D. Long, Volker Blobel, S. D. Talbot, S. W. O'Neale, S. Yamashita, P. Igo-Kemenes, K. Ishii, H. Jeremie, Stephen Lloyd, R. D. Heuer, Robert M Brown, Fabrizio Fabbri, M. J. Pearce, V. Zacek, K. J. Anderson, Georges Azuelos, Reda Tafirout, Klaus Kurt Desch, Kiyotomo Kawagoe, A. Joly, R. Van Kooten, D. Eatough, N. K. Watson, E. Tsur, H. G. Evans, Giora Mikenberg, W. Gorn, C. R. Jones, M. J. Goodrick, P. M. Watkins, Claire Shepherd-Themistocleous, S. B. Anderson, M. Verzocchi, P. Szymanski, Norbert Wermes, K. W. Bell, Sherry Towers, I. Cohen, P. Poffenberger, O. Schaile, M. Schumacher, E. do Couto e Silva, C. Sbarra, E. Lefebvre, P. Vikas, J. Pálinkás, T. Kawamoto, S. Braibant, W. R. Gibson, F. Odorici, A. D. Schaile, F. Wäckerle, N. I. Geddes, D. Lanske, D. M. Gingrich, M. F. Turner-Watson, Michael Hildreth, M. Morii, J. C. Hill, P. Gagnon, Gabriella Pasztor, B. T. Bouwens, Sven Menke, U. Müller, Peter R Hobson, S. Orito, M. Rosvick, John Allison, Dave Charlton, P. Scharff-Hansen, S. R. Lautenschlager, Stan Bentvelsen, W. J. McDonald, N. L. Rodning, H. A. Neal, B. C. Shen, D. Zer-Zion, A. J. Martin, Lorne Levinson, A. Sittler, P. Routenburg, P. Berlich, M. Hapke, B. Poli, K. Nagai, G. A. Snow, C. P. Ward, Sachio Komamiya, Peter Schleper, Gideon Alexander, Theodoros Geralis, A. A. Faust, Stefan Kluth, A. Skillman, R. Bürgin, P. Pfeifenschneider, Paolo Capiluppi, Stefan Schmitt, E. Ros, Siegfried Bethke, T. Hilse, D. R. Rust, D. E. Hutchcroft, R. Lahmann, Shlomit Tarem, A. K. Honma, Silvia Arcelli, D. C. Imrie, C. Y. Chang, S. Söldner-Rembold, A. M. Smith, R. G. Kellogg, C. Hartmann, U. Ruppel, M. R. Ingram, W. G. Scott, Richard Teuscher, A. S. Turcot, O. Runolfsson, D. E. Plane, I. Nakamura, T. P. Kokott, C. K. Hargrove, Stephen Hillier, J. Patt, G. M. Dallavalle, André Schöning, T. Behnke, Csaba Hajdu, F. Fiedler, A. M. Lee, T. Saeki, M. J. Oreglia, P. Taras, E. von Törne, Michael Kobel, S. D. Bird, P. Schenk, Ehud Duchovni, Alan Watson, Stefano Marcellini, G. P. Siroli, C. Beeston, Christoph Schwick, S. Baumann, D. Axen, M. Jimack, S. A. Robins, James Pinfold, A. Jawahery, Claudio Grandi, S. M. Gascon-Shotkin, P. Mättig, D. Glenzinski, J. R. Carter, G. N. Patrick, Allen Mincer, E. A. Mckigney, Gunter Wolf, Julie Kirk, D. G. Fong, A. Michelini, K. Ackerstaff, Dezso Horvath, M. J. Losty, J. Gascon, M. Kolrep, A. Macchiolo, Shoji Asai, B. Stockhausen, Paul Kyberd, F. K. Loebinger, W. P. Lai, Peter Sherwood, Jean-Arcady Meyer, Satoshi Tanaka, J. Steuerer, M. Gruwé, C. M. Hawkes, K. Stephens, Ivor Fleck, I. J. Bloodworth, Alexander Wagner, T. Kobayashi, J. Ludwig, Joleen Pater, J. W. Gary, Paolo Giacomelli, D. S. Koetke, M. Hansroul, K. Runge, P. Bock, A. Klier, Marcello Mannelli, R. Giacomelli, V. Gibson, Richard Nisius, J. M. Roney, C. Burgard, Marco Cuffiani, Yoram Rozen, T. R. Junk, D. I. Futyan, R. J. Homer, I. Trigger, M. Foucher, M. Fierro, J. E.G. Edwards, D. R. Ward, T. Kress, Matthew Evans, D. Karlen, A. M. Rossi, U. Jost, R. Mir, R. Hawkings, F. G. Oakham, B. Schmitt, E. L. Barberio, D. Rigby, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Austin Ball, Peter Krieger, Alessandro Montanari, C. Dallapiccola, N. Altekamp, H. Voss, R. J. Barlow, D. J. Miller, S. Robertson, Gregor Herten, B. Wilkens, J. E. Pilcher, G. W. Wilson, M. Hauschild, C. Markus, G. T. Jones, E. H. Vokurka, N. J. Oldershaw, M. S. Dixit, Frans Meijers, A. Biguzzi, A. Rooke, J. G. Layter, P. E.L. Clarke, M. K. Jones, J. P. Martin, S. De Jong, H. Przysiezniak, A. N. Bell, G. Yekutieli, A. A. Carter, Ron Folman, P. Utzat, Daniele Bonacorsi, O. C. Cooke, J. von Krogh, L. A. del Pozo, T. J. McMahon, R. K. Carnegie, M. Herndon, M. Bobinski, J. A. Wilson, D. Lazic, A. Macpherson, Richard Keeler, R. Bartoldus, R. Howard, J. S. White, H. O. Ogren, Christoph Geich-Gimbel, J. E. Conboy, Vakhtang Kartvelishvili, A. Fürtjes, M. Boutemeur, F. S. Merritt, D. M. Strom, J. Bechtluft, J. A. McKenna, R. Rylko, P. S. Wells, Terry Richard Wyatt, and J. E. Bloomer
Subjects: Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Hadronization, Nuclear physics, Excited state, High Energy Physics::Experiment, Astrophysics::Earth and Planetary Astrophysics, Nuclear Experiment, Particle Physics - Experiment, K channels
Abstract: Results are presented on the production of excited charm and excited charm-strange mesons in hadronic Z(0) decays. The results are obtained from approximately 4.3 million hadronic Z(0) decays, collected on or near the Z(0) resonance using the OPAL detector at LEP. The D-1(0)(2420) and D*(0)(2)(2460) mesons are reconstructed in the D*(+)pi(-) final state and their separate production rates in charm fragmentation and in weak decays of b-hadrons are determined. Assuming that the decay widths of these mesons are saturated by the allowed D*pi and D pi final states, the charm hadronization fractions and the inclusive branching ratios of b-hadrons to these neutral P-wave charm mesons are determined to bef(c --> D-1(0)) = 0.021 +/- 0.007(stat) +/- 0.003(syst), f(c --> D*(0)(2)) = 0.052 +/- 0.022(stat)+/- 0.013(syst), f(b --> D-1(0)) = 0.050 +/- 0.014(stat) +/- 0.006(syst), f(b --> D*(0)(2)) = 0.047 +/- 0.024(stat) +/- 0.013(syst).We also present the first observation at LEP of the D-s1(+)(2536) meson which is reconstructed in both the D*K-+(s)0 and D*K-0(+) final states After correcting for the expected contribution from bb events, assuming that the D*K channels saturate the available final states, these results are used to derive the charm hadronization fraction f(c --> D-s1(+)):f(c --> D-s1(+)) = 0.016 +/- 0.004(stat) +/- 0.003(syst).
Published: 1997
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27. Search for CP violation in Z $^0\longrightarrow{\tau^+\tau^-}$ and an upper limit on the weak dipole moment of the $\tau$ lepton

Author: M. Schumacher, E. Lefebvre, G. W. Wilson, M. Hauschild, S. A. Wotton, C. Markus, G. T. Jones, E. H. Vokurka, F. Odorici, I. J. Bloodworth, A. S. Turcot, F. Fiedler, D. Rigby, R. J. Hemingway, B. W. Kennedy, Yoram Rozen, P. Jovanovic, Austin Ball, Peter Krieger, O. C. Cooke, M. Foucher, R. W. Springer, Manuella Vincter, Alessandro Montanari, M. Kolrep, Matthias Schröder, N. K. Watson, D. Karlen, J. von Krogh, H. Mes, Hans-Christian Schultz-Coulon, I. P. Duerdoth, P. Fath, C. Dallapiccola, Gunter Wolf, K. Ackerstaff, Randall Sobie, A. Biguzzi, Michael Schulz, G. D. Lafferty, Georges Azuelos, N. Altekamp, M. Thiergen, E. Tsur, H. Lafoux, R. J. Barlow, J. M. Roney, Claire Shepherd-Themistocleous, R. Bartoldus, M. Verzocchi, D. J. Miller, Stefan Schmitt, R. J. Hawkings, S. Yamashita, K. W. Bell, P. Igo-Kemenes, J. Pálinkás, K. Ishii, J. Lauber, H. O. Ogren, H. Jeremie, Christoph Geich-Gimbel, L. A. del Pozo, U. Jost, R. Mir, R. E. Hughes-Jones, T. J. Smith, J. C. Hill, K. Stephens, Misao Sasaki, R. Lahmann, Guenter Duckeck, D. C. Imrie, W. Mohr, W. J. McDonald, B. C. Shen, Gideon Bella, H. J. Burckhart, Jacqueline Batley, Paolo Giacomelli, A. Posthaus, P. Mättig, Shoji Asai, V. Gibson, O. Schaile, E. do Couto e Silva, Siegfried Bethke, F. Strumia, S. D. Talbot, G. P. Siroli, A. K. Honma, M. Hansroul, B. Nijjhar, W. G. Scott, T. J. McMahon, Daniel Lellouch, F. G. Oakham, I. Nakamura, Takehiko Mori, B. Schmitt, Abish Malik, T. R. Junk, C. Hartmann, T. Omori, I. Trigger, F. X. Gentit, E. L. Barberio, Kiyotomo Kawagoe, Sven Menke, D. R. Ward, T. Kress, D. E. Plane, S. B. Anderson, P. Szymanski, C. Burgard, Stefan Kluth, R. J. Homer, Shlomit Tarem, U. Müller, V. Zacek, Stephen Hillier, G. M. Dallavalle, J. E. Conboy, D. Chrisman, A. Fürtjes, A. J. Martin, U. Ruppel, M. R. Ingram, R. K. Carnegie, Volker Blobel, T. Behnke, C. R. Jones, M. Herndon, M. Bobinski, J. A. Wilson, D. Glenzinski, Dezso Horvath, M. J. Losty, D. Axen, A. Jawahery, Stan Bentvelsen, Achim Stahl, A. I. McNab, J. Goldberg, Jean-Arcady Meyer, Stephen Lloyd, D. L. Rees, James Pinfold, M. Boutemeur, F. S. Merritt, D. G. Fong, C. Lewis, M. Gruwé, Dave Charlton, A. Wagner, Peter Sherwood, C. M. Hawkes, B. Nellen, C. K. Hargrove, Tara Shears, F. Scharf, J. Gascon, R. Bürgin, German Martinez, J. Ludwig, P. A. Hart, D. Lazic, C. Sbarra, K. Runge, P. Bock, J. W. Gary, J. Bechtluft, J. A. McKenna, Richard Nisius, H. G. Evans, Reda Tafirout, Klaus Kurt Desch, M. J. Goodrick, I. Cohen, M. J. Pearce, D. S. Koetke, Marcello Mannelli, W. Matthews, Marco Cuffiani, K. Ametewee, M. A. Thomson, G. Yekutieli, Andris Skuja, S. Petzold, G. D. Long, Tetsuro Mashimo, P. Pfeifenschneider, E. K. U. Gross, A. Gaidot, J. Patt, Gideon Alexander, Paolo Capiluppi, P. Gagnon, A. A. Carter, Ron Folman, Roger Jones, M. Sproston, W. Gorn, B. J. King, P. Utzat, P. Scharff-Hansen, A. M. Smith, A. Sittler, G. Vasseur, W. R. Gibson, Ehud Duchovni, B. T. Bouwens, M. Jimack, H. M. Bosch, A. Michelini, R. M. Brown, Lorne Levinson, Satoshi Tanaka, T. Kobayashi, A. Skillman, M. F. Turner-Watson, M. Morii, Peter R Hobson, R. Van Kooten, P. Routenburg, F. Wäckerle, D. M. Gingrich, P. Berlich, K. Nagai, J. Grunhaus, D. R. Rust, A. M. Lee, Sachio Komamiya, H. M. Fischer, E. von Törne, Theodoros Geralis, E. Ros, A. T. Watson, T. P. Kokott, S. A. Robins, Robert McPherson, Mathieu Doucet, R. D. Heuer, Fabrizio Fabbri, S. M. Gascon-Shotkin, Matthew Evans, A. M. Rossi, T. Tsukamoto, N. I. Geddes, Michael Hildreth, N. L. Rodning, B. Poli, S. R. Lautenschlager, B. Stockhausen, Paul Kyberd, F. K. Loebinger, H. A. Neal, J. Steuerer, Joleen Pater, T. Hilse, R. Giacomelli, O. Runolfsson, C. Beeston, A. Joly, Claudio Grandi, John Allison, R. G. Kellogg, M. Steiert, Csaba Hajdu, Stefano Marcellini, M. Fierro, J. E.G. Edwards, Ekg Sarkisyan, P. W. Jeffreys, J. J. Ward, P. Vikas, D. Lanske, Silvia Arcelli, E. A. Mckigney, W. P. Lai, P. Schenk, P. G. Estabrooks, R. K. Keeler, N. J. Oldershaw, P. M. Watkins, S. Robertson, Gregor Herten, B. Wilkens, J. E. Pilcher, P. Poffenberger, K. Sachs, Shlomo Dado, Giora Mikenberg, P. Schütz, S. Braibant, A. D. Schaile, Gabriella Pasztor, G. A. Snow, C. P. Ward, S. Söldner-Rembold, R. Howard, J. S. White, C. Y. Chang, D. M. Strom, P. Taras, Michael Kobel, R. Rylko, P. S. Wells, Terry Richard Wyatt, Julie Kirk, J. E. Bloomer, S. W. O'Neale, K. J. Anderson, Otmar Biebel, J. Letts, Norbert Wermes, Sherry Towers, T. Kawamoto, S. Orito, M. Rosvick, M. Hapke, D. E. Hutchcroft, M. J. Oreglia, J. R. Carter, G. N. Patrick, G. G. Hanson, G. Giacomelli, M. S. Dixit, Frans Meijers, P. E.L. Clarke, M. K. Jones, J. P. Martin, S. De Jong, H. Przysiezniak, A. N. Bell, A. Rooke, and J. G. Layter
Subjects: Quark, Physics, Dipole, Particle physics, Physics and Astronomy (miscellaneous), Electron–positron annihilation, Moment (physics), CP violation, Limit (mathematics), Electron, Lepton
Published: 1997
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28. Study of $\phi(1020)$ , ${\rm D}^{\pm}$ and B $^$ spin alignment in hadronic Z $^0$ decays

Author: Achim Stahl, P. Pfeifenschneider, J. Patt, Paolo Giacomelli, M. Hansroul, C. Burgard, R. J. Homer, Ekg Sarkisyan, P. W. Jeffreys, W. R. Gibson, J. J. Ward, P. Vikas, D. Lanske, S. R. Lautenschlager, H. A. Neal, B. T. Bouwens, T. Hilse, O. Runolfsson, R. M. Brown, A. Joly, Lorne Levinson, C. Beeston, Claudio Grandi, Dave Charlton, O. C. Cooke, A. Skillman, Claire Shepherd-Themistocleous, R. Lahmann, R. Bürgin, Reda Tafirout, Klaus Kurt Desch, D. C. Imrie, J. von Krogh, Gideon Bella, H. J. Burckhart, Jacqueline Batley, A. A. Faust, T. Omori, C. R. Jones, Abish Malik, C. Hartmann, D. E. Plane, G. P. Siroli, L. A. del Pozo, Stephen Hillier, U. Jost, G. M. Dallavalle, R. Mir, R. Hawkings, G. Yekutieli, Hans-Christian Schultz-Coulon, Alan Watson, S. G. Clowes, A. Biguzzi, A. Rooke, Randall Sobie, Michael Schulz, G. D. Lafferty, J. G. Layter, S. Yamashita, A. A. Carter, Ron Folman, Roger Jones, F. G. Oakham, T. Behnke, M. Fierro, J. E.G. Edwards, P. Igo-Kemenes, B. Schmitt, E. L. Barberio, J. Letts, K. Ishii, H. Jeremie, P. E.L. Clarke, M. K. Jones, P. Utzat, S. D. Bird, Kiyotomo Kawagoe, F. X. Gentil, A. Macchiolo, M. Gruwé, C. M. Hawkes, R. E. Hughes-Jones, C. Dallapiccola, J. P. Martin, P. Schenk, S. De Jong, U. Müller, T. J. McMahon, Guenter Duckeck, Richard Nisius, D. Axen, O. Schaile, A. J. Martin, K. Sachs, I. J. Bloodworth, Shlomo Dado, R. K. Carnegie, M. Herndon, A. Jawahery, H. Przysiezniak, Marco Cuffiani, E. do Couto e Silva, A. N. Bell, N. Altekamp, Peter Sherwood, K. Ametewee, Sven Menke, Yoram Rozen, R. J. Barlow, H. Mes, I. P. Duerdoth, Gideon Alexander, Alexander Wagner, G. G. Hanson, D. J. Miller, M. Foucher, Paolo Capiluppi, C. K. Hargrove, Tara Shears, J. Ludwig, P. Fath, K. Runge, P. Bock, C. Sbarra, P. A. Hart, Ehud Duchovni, J. Lauber, G. Giacomelli, Otmar Biebel, D. Karlen, M. J. Pearce, M. Jimack, M. S. Dixit, Frans Meijers, A. Michelini, B. Stockhausen, Paul Kyberd, F. K. Loebinger, W. J. McDonald, Daniel Lellouch, S. M. Gascon-Shotkin, B. C. Shen, D. Rigby, R. J. Hemingway, Giora Mikenberg, J. Steuerer, Satoshi Tanaka, T. Kobayashi, Takehiko Mori, Matthias Schröder, Joleen Pater, Siegfried Bethke, A. K. Honma, B. Nijjhar, V. Zacek, W. G. Scott, M. Thiergen, H. Lafoux, S. D. Talbot, I. Nakamura, R. Giacomelli, B. W. Kennedy, M. Schumacher, E. Lefebvre, P. Jovanovic, James Pinfold, D. Eatough, S. B. Anderson, S. Braibant, A. D. Schaile, P. Szymanski, Gabriella Pasztor, Matthew Evans, D. Chrisman, G. D. Long, Austin Ball, F. Odorici, Volker Blobel, Peter Krieger, N. K. Watson, W. Mohr, D. G. Fong, C. Lewis, D. Glenzinski, Dezso Horvath, A. M. Rossi, Stefan Schmitt, M. J. Losty, Jean-Arcady Meyer, G. A. Snow, C. P. Ward, John Allison, Stephen Lloyd, T. Tsukamoto, P. M. Watkins, Manuella Vincter, A. Posthaus, Alessandro Montanari, S. Söldner-Rembold, J. Gascon, T. J. Smith, Stan Bentvelsen, P. Gagnon, P. Mättig, R. W. Springer, W. Matthews, Shoji Asai, Norbert Wermes, Sherry Towers, T. Kawamoto, R. G. Kellogg, M. A. Thomson, E. K. U. Gross, M. Steiert, A. Sittler, Csaba Hajdu, A. Gaidot, Georges Azuelos, M. Sproston, P. Poffenberger, A. S. Turcot, Stefano Marcellini, S. Orito, E. Tsur, H. M. Bosch, F. Fiedler, M. Verzocchi, Silvia Arcelli, K. W. Bell, J. Pálinkás, M. Rosvick, J. C. Hill, J. W. Gary, Misao Sasaki, N. I. Geddes, Michael Hildreth, D. S. Koetke, M. Hapke, Marcello Mannelli, E. A. Mckigney, D. E. Hutchcroft, P. Schütz, M. Kolrep, N. L. Rodning, W. P. Lai, D. L. Rees, B. Poli, M. J. Oreglia, F. Scharf, German Martinez, J. M. Roney, H. M. Fischer, J. R. Carter, G. N. Patrick, S. A. Robins, Stefan Kluth, P. O. Estabrooks, Shlomit Tarem, A. I. McNab, J. Goldberg, B. Nellen, H. G. Evans, S. W. O'Neale, M. J. Goodrick, I. Cohen, Gunter Wolf, K. Ackerstaff, K. J. Anderson, C. Y. Chang, P. Taras, Michael Kobel, Julie Kirk, K. Stephens, V. Gibson, T. R. Junk, I. Trigger, D. R. Ward, T. Kress, U. Ruppel, M. R. Ingram, S. Robertson, Gregor Herten, B. Wilkens, P. S. Wells, J. E. Pilcher, N. J. Oldershaw, Terry Richard Wyatt, J. E. Bloomer, G. W. Wilson, M. Hauschild, S. A. Wotton, C. Markus, G. T. Jones, E. H. Vokurka, M. Fanti, D. M. Strom, M. Boutemeur, F. S. Merritt, Robert McPherson, R. Rylko, Mathieu Doucet, R. D. Heuer, J. Bechtluft, J. A. McKenna, Fabrizio Fabbri, M. Bobinski, J. A. Wilson, A. Macpherson, R. Bartoldus, P. Scharff-Hansen, R. Van Kooten, Richard Keeler, H. O. Ogren, Christoph Geich-Gimbel, D. Lazic, J. E. Conboy, A. Fürtjes, R. Howard, A. M. Smith, J. S. White, J. Grunhaus, G. Vasseur, F. Wäckerle, Andris Skuja, D. M. Gingrich, Sachio Komamiya, S. Petzold, Theodoros Geralis, E. Ros, Tetsuro Mashimo, P. Berlich, T. P. Kokott, K. Nagai, D. R. Rust, W. Gorn, M. F. Turner-Watson, M. Morii, Peter R Hobson, D. Zer-Zion, P. Routenburg, A. M. Lee, and E. von Törne
Subjects: Quark, Physics, Density matrix, Particle physics, Physics and Astronomy (miscellaneous), Meson, Electron–positron annihilation, Hadron, D-STAR, Polarization (waves), Helicity, Nuclear physics, High Energy Physics::Experiment, Particle Physics - Experiment
Abstract: Measurements of helicity density matrix elements have been made for the φ(1020), D*± and B* vector mesons in multihadronic Z0 decays in the OPAL experiment at LEP. Results for inclusive φ produced with high energy show evidence for production preferentially in the helicity zero state, with ρ00 = 0.54 ± 0.08, compared to the value of 1/3 expected for no spin alignment. The corresponding element for the D*± has a value of 0.40 ± 0.02, also suggesting a deviation from 1/3. The B* result, with ρ00 = 0.36 ± 0.09, is consistent with no spin alignment. Off-diagonal elements have been measured for the f and D* mesons; for the D* the element Re ρ1−1 is non-zero, indicating non-independent fragmentation of the primary quarks.
Published: 1997
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29. A measurement of |Vcb| using decays

Author: A. I. McNab, A. S. Turcot, J. Goldberg, F. Fiedler, S. Yamashita, B. Nellen, P. Igo-Kemenes, Gideon Bella, H. J. Burckhart, K. Ishii, Jacqueline Batley, H. Jeremie, R. E. Hughes-Jones, M. Kolrep, K. Sachs, Shlomo Dado, M. F. Turner-Watson, M. Morii, H. G. Evans, P. Schenk, P. E.L. Clarke, M. K. Jones, Peter R Hobson, O. Schaile, M. Hapke, Achim Stahl, G. Azuelos, M. J. Goodrick, I. Cohen, J. P. Martin, S. De Jong, E. do Couto e Silva, P. Routenburg, R. Van Kooten, H. Przysiezniak, Sachio Komamiya, T. Omori, D. E. Hutchcroft, O. C. Cooke, A. N. Bell, Theodoros Geralis, E. Ros, A. T. Watson, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, G. G. Hanson, G. Giacomelli, Reda Tafirout, Klaus Kurt Desch, Giora Mikenberg, M. S. Dixit, Frans Meijers, Sven Menke, C. Y. Chang, P. G. Estabrooks, C. R. Jones, M. J. Oreglia, T. P. Kokott, A. Rooke, J. G. Layter, J. von Krogh, W. Matthews, P. S. Wells, P. Taras, Michael Kobel, Gunter Wolf, F. X. Gentit, A. J. Martin, R. K. Keeler, F. Wäckerle, Ekg Sarkisyan, P. W. Jeffreys, R. J. Hawkings, K. Ackerstaff, Terry Richard Wyatt, D. M. Gingrich, H. Mes, M. A. Thomson, J. E. Bloomer, M. Boutemeur, Ehud Duchovni, D. Rigby, R. J. Hemingway, S. Braibant, J. E.G. Edward, Julie Kirk, H. M. Fischer, T. Behnke, Guenter Duckeck, M. Jimack, P. Fath, L. A. del Pozo, C. Sbarra, U. Ruppel, M. R. Ingram, Matthias Schröder, A. D. Schaile, Gabriella Pasztor, P. Berlich, W. R. Gibson, P. M. Watkins, Paolo Giacomelli, M. Thiergen, E. K. U. Gross, J. R. Carter, J. Grunhaus, G. Yekutieli, G. N. Patrick, J. Bechtluft, A. Michelini, J. A. McKenna, Dave Charlton, B. T. Bouwens, M. Hansroul, P. Poffenberger, M. Gruwé, C. M. Hawkes, A. A. Carter, J. J. Ward, B. Stockhausen, Paul Kyberd, P. Vikas, S. B. Anderson, G. A. Snow, C. P. Ward, F. K. Loebinger, P. Szymanski, Ron Folman, Roger Jones, B. W. Kennedy, P. Jovanovic, R. M. Brown, Lorne Levinson, Otmar Biebel, Satoshi Tanaka, T. Kobayashi, C. Burgard, D. Lanske, P. Schütz, R. J. Homer, I. J. Bloodworth, R. Bartoldus, S. Söldner-Rembold, B. J. King, H. O. Ogren, P. Utzat, Christoph Geich-Gimbel, R. Bürgin, Richard Nisius, A. Gaidot, A. Skillman, Austin Ball, J. Steuerer, F. S. Merritt, D. M. Strom, T. J. McMahon, Stan Bentvelsen, Peter Krieger, M. S. Proston, Marco Cuffiani, LP Duerdoth, Stefan Kluth, C. Hartmann, D. E. Plane, Shlomit Tarem, R. K. Carnegie, M. Schumacher, Joleen Pater, E. Lefebvre, S. Robertson, P. Pfeifenschneider, Stephen Hillier, Gregor Herten, U. Müller, Silvia Arcelli, J. Letts, M. Herndon, G. M. Dallavalle, S. A. Robins, J. E. Conboy, A. Fürtjes, M. Bobinski, J. A. Wilson, R. Rylko, J. Patt, F. Odorici, Manuella Vincter, Norbert Wermes, Alessandro Montanari, Sherry Towers, N. K. Watson, B. Wilkens, K. Ametewee, T. Kawamoto, R. Giacomelli, Robert McPherson, M. Fierro, S. W. O'Neale, A. Biguzzi, Gideon Alexander, K. J. Anderson, Paolo Capiluppi, D. Lazic, S. Orito, S. R. Lautenschlager, H. A. Neal, U. Jost, R. Mir, E. A. Mckigney, M. Rosvick, Yoram Rozen, J. E. Pilcher, Mathieu Doucet, C. K. Hargrove, R. D. Heuer, M. Foucher, D. Chrisman, Tara Shears, Claire Shepherd-Themistocleous, T. Hilse, W. P. Lai, O. Runolfsson, W. Mohr, N. J. Oldershaw, Volker Blobel, Fabrizio Fabbri, P. A. Hart, T. J. Smith, A. Posthaus, K. Stephens, J. M. Roney, C. Beeston, Stephen Lloyd, M. J. Pearce, R. Howard, J. S. White, Claudio Grandi, K. Nagai, F. G. Oakham, B. Schmitt, E. L. Barberio, D. R. Rust, V. Gibson, C. Dallapiccola, D. Karlen, D. L. Rees, T. R. Junk, N. Altekamp, A. Joly, I. Trigger, R. J. Barlow, D. R. Ward, H. Lafoux, D. J. Miller, T. Kress, F. Scharf, German Martinez, A. K. Honma, Daniel Lellouch, G. W. Wilson, M. Hauschild, A. M. Lee, S. A. Wotton, Takehiko Mori, C. Markus, E. von Törne, G. T. Jones, E. H. Vokurka, V. Zacek, R. Lahmann, John Allison, D. C. Imrie, Stefan Schmitt, N. I. Geddes, Michael Hildreth, R. G. Kellogg, M. Steiert, P. Mättig, Shoji Asai, Csaba Hajdu, G. P. Siroli, Stefano Marcellini, N. L. Rodning, B. Poli, S. M. Gascon-Shotkin, Kiyotomo Kawagoe, Matthew Evans, A. M. Rossi, T. Tsukamoto, P. Scharff-Hansen, A. M. Smith, D. Axen, A. Jawahery, G. Vasseur, Peter Sherwood, Andris Skuja, Alexander Wagner, S. Petzold, J. Ludwig, G. D. Long, K. Runge, P. Bock, Tetsuro Mashimo, J. Lauber, W. Gorn, F. Strumia, S. D. Talbot, James Pinfold, D. G. Fong, C. Lewis, J. Gascon, W. J. McDonald, A. Malik, B. C. Shen, J. W. Gary, D. S. Koetke, Marcello Mannelli, P. Gagnon, A. Sittler, Siegfried Bethke, B. Nijjhar, W. G. Scott, I. Nakamura, H. M. Bosch, D. Glenzinski, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, R. W. Springer, E. Tsur, M. Verzocchi, K. W. Bell, J. Pálinkás, J. C. Hill, and Misao Sasaki
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Muon, Meson, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Form factor (quantum field theory), Electron, Rest frame, Nuclear physics, Recoil, High Energy Physics::Experiment, Nuclear Experiment
Abstract: We report a measurement of the Cabibbo-Kobayashi-Maskawa matrix element |Vcb|. From approximately 4.2 million hadronic Z0 decays recorded with the OPAL deteector, a sample is selected containing 1251 ± 125 B 0 → D ∗+ l − ν l candidates, where l is either an electron or a muon. Using Heavy Quark Effective Theory calculations for the decay form factor at zero recoil of the D∗+ meson in the B 0 rest frame, we derive |Vcb| = [36.0 ± 2.1 (stat) ± 2.4 (syst) ± 1.2 (theory)] × 10−3.
Published: 1997
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30. An improved measurement of $R_b$ using a double tagging method

Author: S. Yamashita, P. Igo-Kemenes, Richard Keeler, D. M. Strom, R. Howard, R. Rylko, K. Ishii, H. Jeremie, R. E. Hughes-Jones, C. Dallapiccola, Takehiko Mori, M. Hapke, H. Mes, I. P. Duerdoth, P. S. Wells, A. Biguzzi, Terry Richard Wyatt, J. E. Bloomer, V. Zacek, D. E. Hutchcroft, P. Fath, O. Schaile, Silvia Arcelli, Claire Shepherd-Themistocleous, E. do Couto e Silva, Dave Charlton, B. Stockhausen, Paul Kyberd, F. K. Loebinger, K. Sachs, Shlomo Dado, Robert McPherson, N. Altekamp, J. Steuerer, Sven Menke, R. Bürgin, Mathieu Doucet, E. A. Mckigney, Joleen Pater, Stefan Schmitt, R. D. Heuer, R. J. Barlow, A. S. Turcot, M. J. Oreglia, R. Giacomelli, T. J. Smith, Stefan Kluth, Fabrizio Fabbri, W. P. Lai, F. Fiedler, Shlomit Tarem, Giora Mikenberg, D. J. Miller, T. Behnke, P. Mättig, Shoji Asai, J. Grunhaus, J. M. Roney, K. Nagai, I. J. Bloodworth, S. Braibant, John Allison, A. D. Schaile, T. Kawamoto, Gabriella Pasztor, Gideon Bella, D. R. Rust, Kiyotomo Kawagoe, H. J. Burckhart, P. Gagnon, M. Schumacher, E. Lefebvre, M. Gruwé, Andris Skuja, M. Kolrep, Jacqueline Batley, J. R. Carter, G. N. Patrick, S. Petzold, P. Schenk, C. M. Hawkes, K. Ackerstaff, G. D. Long, K. Stephens, R. G. Kellogg, Yoram Rozen, M. Steiert, F. Odorici, G. A. Snow, C. P. Ward, Tetsuro Mashimo, Otmar Biebel, Csaba Hajdu, T. Omori, A. Sittler, P. G. Estabrooks, A. M. Lee, Richard Nisius, P. Poffenberger, Stefano Marcellini, M. Foucher, S. B. Anderson, S. Söldner-Rembold, P. Szymanski, E. von Törne, S. Robertson, V. Gibson, P. M. Watkins, H. M. Bosch, C. R. Jones, Marco Cuffiani, D. Karlen, Gregor Herten, W. Gorn, D. Rigby, R. J. Hemingway, A. Joly, G. W. Wilson, J. Letts, Stan Bentvelsen, U. Müller, Norbert Wermes, T. R. Junk, A. J. Martin, Sherry Towers, A. I. McNab, P. Schütz, J. Goldberg, D. Axen, I. Trigger, R. Van Kooten, A. Jawahery, Hans-Christian Schultz-Coulon, B. Nellen, Randall Sobie, Michael Schulz, G. D. Lafferty, M. F. Turner-Watson, S. Orito, B. Wilkens, D. R. Ward, T. Kress, M. Morii, B. W. Kennedy, James Pinfold, M. Rosvick, Achim Stahl, Peter R Hobson, P. Jovanovic, U. Ruppel, Peter Sherwood, R. Lahmann, M. R. Ingram, D. G. Fong, C. Lewis, P. Routenburg, Alexander Wagner, H. G. Evans, M. J. Goodrick, J. Gascon, C. K. Hargrove, Guenter Duckeck, Sachio Komamiya, Theodoros Geralis, E. Ros, J. E. Pilcher, Austin Ball, J. Ludwig, K. Runge, I. Cohen, P. Bock, G. P. Siroli, Matthias Schröder, N. I. Geddes, J. Lauber, N. J. Oldershaw, Peter Krieger, Michael Hildreth, M. Thiergen, H. Lafoux, T. P. Kokott, J. W. Gary, D. S. Koetke, E. Gross, Marcello Mannelli, D. Lellouch, N. L. Rodning, F. Strumia, S. D. Talbot, F. Wäckerle, B. Poli, Manuella Vincter, D. M. Gingrich, P. Scharff-Hansen, Alessandro Montanari, Tara Shears, P. A. Hart, A. M. Smith, S. M. Gascon-Shotkin, U. Jost, P. Berlich, R. Mir, G. Vasseur, M. J. Pearce, Matthew Evans, A. M. Rossi, M. Hauschild, T. Tsukamoto, Paolo Giacomelli, S. W. O'Neale, M. Hansroul, K. J. Anderson, S. A. Wotton, C. Markus, H. M. Fischer, G. T. Jones, E. H. Vokurka, C. Y. Chang, F. G. Oakham, B. Schmitt, S. A. Robins, C. Burgard, E. L. Barberio, R. J. Homer, P. Taras, Michael Kobel, P. Pfeifenschneider, Julie Kirk, J. Patt, F. S. Merritt, J. Bechtluft, J. A. McKenna, R. Bartoldus, H. O. Ogren, Christoph Geich-Gimbel, J. E. Conboy, N. K. Watson, F. X. Gentit, A. Fürtjes, W. Mohr, W. J. McDonald, B. C. Shen, Siegfried Bethke, A. K. Honma, B. Nijjhar, A. Posthaus, W. G. Scott, I. Nakamura, D. Glenzinski, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, R. W. Springer, D. L. Rees, Georges Azuelos, E. Tsur, M. Verzocchi, K. W. Bell, J. Pálinkás, J. C. Hill, Misao Sasaki, F. Scharf, German Martinez, W. Matthews, M. A. Thomson, A. Gaidot, M. Sproston, C. Sbarra, G. Yekutieli, A. A. Carter, Ron Folman, Roger Jones, B. J. King, P. Utzat, T. J. McMahon, R. K. Carnegie, M. Herndon, M. Bobinski, J. A. Wilson, D. Lazic, O. C. Cooke, J. von Krogh, R. J. Hawkings, L. A. del Pozo, Ehud Duchovni, M. Jimack, A. Michelini, D. C. Imrie, Satoshi Tanaka, J. S. White, M. Boutemeur, T. Kobayashi, M. Fierro, J. E.G. Edwards, S. R. Lautenschlager, H. A. Neal, T. Hilse, O. Runolfsson, D. Chrisman, Volker Blobel, C. Beeston, Claudio Grandi, Stephen Lloyd, Ekg Sarkisyan, P. W. Jeffreys, Robert M Brown, K. Ametewee, Gideon Alexander, Paolo Capiluppi, J. J. Ward, P. Vikas, D. Lanske, W. R. Gibson, B. T. Bouwens, Lorne Levinson, A. Skillman, Abish Malik, C. Hartmann, D. E. Plane, Stephen Hillier, G. M. Dallavalle, Alan Watson, G. G. Hanson, Reda Tafirout, Klaus Kurt Desch, G. Wolf, G. Giacomelli, M. S. Dixit, Frans Meijers, P. E.L. Clarke, M. K. Jones, J. P. Martin, S. De Jong, H. Przysiezniak, A. N. Bell, A. Rooke, and J. G. Layter
Subjects: Nuclear physics, Physics, Top quark, Particle physics, Physics and Astronomy (miscellaneous), Meson, Bottom quark, Particle Physics - Experiment
Published: 1997
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31. Measurement of the triple gauge boson coupling αW from W+W− production in e+e− collisions at =161GeV

Author: S. A. Robins, J. R. Carter, Michael Hildreth, R. Bartoldus, N. L. Rodning, B. Poli, K. Nagai, N. K. Watson, Otmar Biebel, Shigenori Tanaka, S. M. Gascon-Shotkin, U. Müller, P. Igo-Kemenes, S. R. Lautenschlager, H. A. Neal, D. R. Rust, Matthew Evans, A. M. Rossi, T. Tsukamoto, H. O. Ogren, Christoph Geich-Gimbel, A. J. Martin, K. Ishii, H. Jeremie, T. Hilse, R. E. Hughes-Jones, M. Schumacher, E. Lefebvre, T. Behnke, O. C. Cooke, V. Gibson, A. Biguzzi, O. Runolfsson, Gideon Bella, A. M. Lee, H. J. Burckhart, E. von Törne, Jacqueline Batley, J. Letts, James Pinfold, W. Matthews, U. Ruppel, M. R. Ingram, D. G. Fong, C. Lewis, O. Schaile, F. Odorici, E. do Couto e Silva, S. Robertson, S. L. Lloyd, P. Schütz, P. Gagnon, A. Rooke, J. G. Layter, J. E. Conboy, A. Fürtjes, Gregor Herten, J. Allison, C. K. Hargrove, C. Hartmann, K. Ametewee, J. Gascon, D. E. Plane, A. Macchiolo, Sven Menke, Matthias Schröder, A. Sittler, B. Wilkens, T. Omori, Gideon Alexander, M. Sasaki, J. Palinkas, Norbert Wermes, Sherry Towers, Paolo Capiluppi, M. A. Thomson, Claudio Grandi, M. Thiergen, K. Sachs, M. Boutemeur, F. S. Merritt, T. Kawamoto, V. Zacek, R. Van Kooten, J. A. McKenna, Stephen Hillier, J. E. Pilcher, Shlomo Dado, C. R. Jones, G. M. Dallavalle, Ekg Sarkisyan, Richard Nisius, P. W. Jeffreys, J. Bechtluft, S. Orito, H. M. Bosch, M. Rosvick, S. W. O'Neale, J. von Krogh, D. S. Koetke, G. W. Wilson, T. Kobayashi, Marcello Mannelli, G. G. Hanson, H. Mes, M. Hauschild, R. G. Kellogg, M. Steiert, I. P. Duerdoth, R. W.L. Jones, S. A. Wotton, Marco Cuffiani, P. Fath, D. Chrisman, G. D. Long, E. K. U. Gross, Kiyotomo Kawagoe, C. Markus, D. M. Strom, C.J. Beeston, Csaba Hajdu, G. Giacomelli, J. Lauber, Volker Blobel, M. Hapke, Dave Charlton, K. J. Anderson, T. G. Shears, Stefano Marcellini, P. Scharff-Hansen, G. T. Jones, E. H. Vokurka, P. A. Hart, G. Mikenberg, T. J. Smith, N. J. Oldershaw, B. Nijjhar, M. J. Pearce, F. Wäckerle, Joleen Pater, M. Sproston, Claire Shepherd-Themistocleous, K. Stephens, L. A. del Pozo, C. Y. Chang, D. M. Gingrich, B. Stockhausen, Paul Kyberd, F. K. Loebinger, A. M. Smith, M. S. Dixit, Frans Meijers, R. Bürgin, M. J. Oreglia, W. R. Gibson, P. Taras, Michael Kobel, J. Steuerer, J. J. Ward, S. D. Talbot, Ehud Duchovni, R. Rylko, P. E.L. Clarke, M. K. Jones, P. Vikas, S. Braibant, A. D. Schaile, A. A. Faust, B. T. Bouwens, M. Jimack, P. Berlich, P. Poffenberger, M. Fanti, Andris Skuja, J. P. Martin, Gabriella Pasztor, R. Giacomelli, R. Lahmann, Julie Kirk, D. Lanske, A. Michelini, Gunter Wolf, K. Ackerstaff, Satoru Yamashita, S. Petzold, D. Eatough, S. De Jong, G. Yekutieli, Tetsuro Mashimo, G. N. Patrick, D. C. Imrie, R. M. Brown, Lorne Levinson, T. R. Junk, H. Przysiezniak, G. A. Snow, C. P. Ward, A. A. Carter, Ron Folman, Robert McPherson, G. P. Siroli, A. N. Bell, I. Trigger, A. Skillman, A. Joly, Mathieu Doucet, S. Söldner-Rembold, W. Gorn, S. D. Bird, R. D. Heuer, N. I. Geddes, P. Schenk, C. Sbarra, P. S. Wells, Fabrizio Fabbri, D. R. Ward, T. Kress, D. L. Rees, P. Utzat, A. T. Watson, Reda Tafirout, Klaus Kurt Desch, J. E. Bloomer, F. Scharf, German Martinez, D. Axen, A. I. McNab, A. Macpherson, J. Goldberg, A. Jawahery, T. R. Wyatt, T. J. McMahon, J. M. Roney, R. J. Sobie, B. Nellen, R. K. Carnegie, M. Herndon, R. Howard, M. Bobinski, R. J. Barlow, J. A. Wilson, J. S. White, W. Mohr, Peter Sherwood, A. Posthaus, D. Lazic, Alexander Wagner, M. Fierro, J. E.G. Edwards, J. Ludwig, K. Runge, P. Bock, H. G. Evans, M. J. Goodrick, I. Cohen, Stefan Kluth, Shlomit Tarem, R. W. Springer, Achim Stahl, Daniel Lellouch, Paolo Giacomelli, M. Hansroul, C. Burgard, Takehiko Mori, R. J. Homer, Georges Azuelos, E. Tsur, C. M. Hawkes, P. Pfeifenschneider, J. Patt, M. Verzocchi, K. W. Bell, J. C. Hill, B. C. Shen, Siegfried Bethke, A. K. Honma, W. G. Scott, I. Nakamura, J. W. Gary, D. Glenzinski, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, Sachio Komamiya, Stefan Schmitt, Theodoros Geralis, M. Gruwe, E. Ros, U. Jost, R. Mir, T. P. Kokott, R. Hawkings, W.J. McDonald, P. Mättig, Shoji Asai, J. Grunhaus, I. J. Bloodworth, S. B. Anderson, P. Szymanski, Stan Bentvelsen, F. G. Oakham, Hans-Christian Schultz-Coulon, B. Schmitt, E. L. Barberio, Michael Schulz, Yoram Rozen, G. Duckeck, M. Foucher, M. F. Turner-Watson, M. Morii, Peter R Hobson, D. Zer-Zion, P. Routenburg, D. Karlen, D. Rigby, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, A. S. Turcot, F. Fiedler, Austin Ball, Peter Krieger, Manuella Vincter, Alessandro Montanari, M. Kolrep, D. E. Hutchcroft, C. Dallapiccola, N. Altekamp, D. J. Miller, P. G. Estabrooks, R. K. Keeler, P. M. Watkins, Silvia Arcelli, E. A. Mckigney, W. P. Lai, G. D. Lafferty, and H. M. Fischer
Subjects: Semileptonic decay, Coupling, Physics, Nuclear and High Energy Physics, Particle physics, Gauge boson, Luminosity (scattering theory), Electron–positron annihilation, law.invention, Standard Model, Nuclear physics, Coupling parameter, law, High Energy Physics::Experiment, Collider
Abstract: This letter describes a measurement of one of the anomalous triple gauge boson couplings using the first data recorded by the OPAL detector at LEP2. A total of 28 W-pair candidates have been selected for an integrated luminosity of 9.89+/-0.06 pb(-1) recorded at a centre-of-mass energy of 161 GeV. We use these data to place constraints upon the coupling parameter alpha(W phi). We analyse the predicted variation of the total cross-section for all observed channels and the distribution of kinematic variables in the semileptonic decay channels. We measure alpha(W phi) to be -0.61(-0.61)(+0.73)+/-0.35, which is consistent with the Standard Model expectation of zero. (C) 1997 Published by Elsevier Science B.V.
Published: 1997
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32. Search for charged scalar leptons using the OPAL detector at GeV

Author: D. Rigby, R. J. Hemingway, V Zacek, B. W. Kennedy, R. Bartoldus, R. Lahmann, D. C. Imrie, G. P. Siroli, John Allison, P. Jovanovic, Austin Ball, J. Grunhaus, Christoph Geich-Gimbel, Peter Krieger, Manuella Vincter, Alessandro Montanari, D. Axen, A. Jawahery, R. G. Kellogg, M. Steiert, Gunter Wolf, Tara Shears, A. Biguzzi, K. Ackerstaff, Peter Sherwood, Alexander Wagner, Csaba Hajdu, K. Sachs, Shlomo Dado, I. J. Bloodworth, J. E. Conboy, A. Fürtjes, J. Ludwig, Claire Shepherd-Themistocleous, H.O Ogren, Stefano Marcellini, S. Robertson, K. Runge, P. Bock, Gregor Herten, Yoram Rozen, M. Foucher, P. A. Hart, Gideon Bella, M. J. Pearce, B. Wilkens, Giora Mikenberg, D. Karlen, H. J. Burckhart, Jacqueline Batley, Sachio Komamiya, Theodoros Geralis, E. Ros, A. T. Watson, T. Behnke, Daniel Lellouch, S. Braibant, A. D. Schaile, J. E. Pilcher, T. P. Kokott, G. Azuelos, Takehiko Mori, C. Sbarra, T. Omori, Gabriella Pasztor, R. W. Springer, M. Gruwé, C. M. Hawkes, G. A. Snow, C. P. Ward, G. Yekutieli, G. G. Hanson, C. R. Jones, U. Müller, S. Söldner-Rembold, P. Gagnon, Richard Nisius, A. A. Carter, Ron Folman, Roger Jones, A. Sittler, G. Giacomelli, C. Dallapiccola, Stefan Schmitt, A. I. McNab, J. Goldberg, Silvia Arcelli, Marco Cuffiani, H. M. Bosch, B. Nellen, B. J. King, M. Boutemeur, F. S. Merritt, Reda Tafirout, Klaus Kurt Desch, E. Tsur, M. S. Dixit, A. J. Martin, S. W. O'Neale, P. Utzat, Frans Meijers, Dave Charlton, M. Verzocchi, A. S. Turcot, F. Fiedler, J. Lauber, K. J. Anderson, P. Mättig, S Anderson, M. F. Turner-Watson, K. W. Bell, M. Morii, J. Pálinkás, A. Rooke, Peter R Hobson, J. G. Layter, Shoji Asai, P. Routenburg, R. Bürgin, N. Altekamp, F. Strumia, G. W. Wilson, E. A. Mckigney, S. D. Talbot, O. C. Cooke, M. Hauschild, J. C. Hill, S. A. Wotton, P. Poffenberger, W. R. Gibson, Misao Sasaki, H. G. Evans, J. Bechtluft, R. J. Barlow, W. P. Lai, J. A. McKenna, M. J. Goodrick, P. E.L. Clarke, D. J. Miller, C. Markus, M. K. Jones, P. Schütz, B. T. Bouwens, J. P. Martin, I. Cohen, M. Kolrep, S. De Jong, G. T. Jones, E. H. Vokurka, R. M. Brown, Lorne Levinson, A. Joly, J. M. Roney, J. von Krogh, C. K. Hargrove, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, H. Przysiezniak, N. J. Oldershaw, C. Y. Chang, A. N. Bell, M. Hapke, P. Schenk, Paolo Giacomelli, D. E. Hutchcroft, A. Skillman, P. Taras, Michael Kobel, M. Hansroul, B. Stockhausen, Paul Kyberd, F. K. Loebinger, C. Hartmann, D. E. Plane, P. S. Wells, Stephen Hillier, Julie Kirk, J. Steuerer, Joleen Pater, R. J. Hawkings, Guenter Duckeck, C. Burgard, W. J. McDonald, G. M. Dallavalle, B. C. Shen, Terry Richard Wyatt, M. J. Oreglia, R. Giacomelli, L. A. del Pozo, R. J. Homer, Siegfried Bethke, A. K. Honma, B. Nijjhar, W. G. Scott, J. E. Bloomer, I. Nakamura, Andris Skuja, S. Petzold, G. D. Long, Tetsuro Mashimo, D. Glenzinski, Dezso Horvath, M. J. Losty, N. I. Geddes, Michael Hildreth, Jean-Arcady Meyer, U. Jost, R. Mir, Stefan Kluth, J. R. Carter, N. L. Rodning, Shlomit Tarem, B. Poli, G. N. Patrick, W. Gorn, P. Szymanski, Matthias Schröder, F. G. Oakham, B. Schmitt, Otmar Biebel, M. Thiergen, E. L. Barberio, S. M. Gascon-Shotkin, Stan Bentvelsen, P. Pfeifenschneider, R. Howard, J. S. White, J. Patt, Matthew Evans, A. M. Rossi, T. Tsukamoto, J. Letts, H. M. Fischer, D. M. Strom, Norbert Wermes, Sherry Towers, T. Kawamoto, P. Scharff-Hansen, R. Rylko, S. A. Robins, S. Orito, M. Rosvick, A. M. Smith, Achim Stahl, James Pinfold, D. G. Fong, C. Lewis, J. Gascon, J. W. Gary, D. S. Koetke, Marcello Mannelli, Ekg Sarkisyan, P. W. Jeffreys, J. J. Ward, P. Vikas, D. Lanske, S. R. Lautenschlager, H. A. Neal, T. Hilse, T. J. McMahon, O. Runolfsson, R. K. Carnegie, M. Herndon, C. Beeston, U. Ruppel, Claudio Grandi, M. Bobinski, J. A. Wilson, M. R. Ingram, D. Lazic, M. Fierro, J. E.G. Edwards, T. J. Smith, K. Stephens, V. Gibson, T. R. Junk, I. Trigger, D. R. Ward, T. Kress, D. Chrisman, Volker Blobel, Stephen Lloyd, S. Yamashita, P. Igo-Kemenes, Ehud Duchovni, K. Ishii, H. Jeremie, M. Jimack, A. Michelini, R. E. Hughes-Jones, O. Schaile, E. do Couto e Silva, Satoshi Tanaka, T. Kobayashi, Sven Menke, K. Ametewee, Gideon Alexander, Paolo Capiluppi, P. G. Estabrooks, R. K. Keeler, P. M. Watkins, Kiyotomo Kawagoe, D. L. Rees, F. Scharf, German Martinez, N. K. Watson, W. Mohr, A. Posthaus, H. Mes, I. P. Duerdoth, P. Fath, R. Van Kooten, W. Matthews, M. A. Thomson, E. K. U. Gross, M. Sproston, F. Wäckerle, D. M. Gingrich, P. Berlich, M. Schumacher, E. Lefebvre, F. Odorici, K. Nagai, D. R. Rust, A. M. Lee, E. von Törne, Robert McPherson, Mathieu Doucet, R. D. Heuer, and Fabrizio Fabbri
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Missing energy, Muon, High Energy Physics::Phenomenology, Detector, Scalar (physics), Electron, Nuclear physics, Selectron tube, High Energy Physics::Experiment, Minimal Supersymmetric Standard Model, Lepton
Abstract: A search for pair-produced scalar electron, muon and tau leptons has been performed using a data sample corresponding to an integrated luminosity of 10.1 pb−1 at a centre-of-mass energy of s =161 GeV collected with the OPAL detector at LEP. Such events would yield an acoplanar pair of leptons with significant missing energy in the final state. No excess of acoplanar lepton pair events has been observed in the data. Limits are presented on the production cross-sections of charged scalar leptons. Exclusion regions are also presented in the framework of the Minimal Supersymmetric Standard Model. A 95% C.L. lower limit on the right-handed selectron mass of 71.5 GeV is obtained for tan β ≥ 1.5, |μ| ≥ 200 GeV and m χ 1 0 = 12.0 GeV . A 95% C.L. lower limit on the right-handed smuon mass of 51.0 GeV is obtained for m χ 1 0 = 12.0 GeV , independent of tan β and μ.
Published: 1997
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33. Search for the Standard Model Higgs boson in e+e− collisions at =161

Author: C. Y. Chang, K. W. Bell, P. Taras, Michael Kobel, R. W. Springer, N. K. Watson, Julie Kirk, Reda Tafirout, Klaus Kurt Desch, D. Rigby, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Austin Ball, Peter Krieger, Manuella Vincter, Alessandro Montanari, Robert McPherson, E. Tsur, James Pinfold, U. Jost, R. Mir, F. G. Oakham, B. Schmitt, Mathieu Doucet, R. D. Heuer, Ekg Sarkisyan, M. Verzocchi, J. Pálinkás, C. Hartmann, D. E. Plane, W. Mohr, D. G. Fong, C. Lewis, E. L. Barberio, M. Boutemeur, F. S. Merritt, A. Posthaus, J. C. Hill, J. Gascon, Stephen Hillier, G. M. Dallavalle, A. S. Turcot, F. Fiedler, C. Dallapiccola, Fabrizio Fabbri, J. Grunhaus, Kiyotomo Kawagoe, Misao Sasaki, W. J. McDonald, B. C. Shen, Dave Charlton, S. M. Gascon-Shotkin, Otmar Biebel, P. W. Jeffreys, W. Matthews, A. Biguzzi, N. Altekamp, R. J. Barlow, D. J. Miller, T. J. Smith, K. Stephens, G. W. Wilson, M. Hauschild, R. Van Kooten, M. A. Thomson, D. Glenzinskj, Claire Shepherd-Themistocleous, Siegfried Bethke, A. K. Honma, B. Nijjhar, W. G. Scott, I. Nakamura, S. A. Wotton, S. Braibant, A. D. Schaile, Gabriella Pasztor, E. K. U. Gross, R. Bürgin, H. Mes, C. Markus, V. Gibson, M. Sproston, J. W. Gary, D. S. Koetke, J. A. McKenna, A. Rooke, G. T. Jones, T. R. Junk, I. P. Duerdoth, Sachio Komamiya, Theodoros Geralis, E. Ros, A. T. Watson, Matthew Evans, P. Fath, J. Letts, Dezso Horvath, M. J. Losty, E. H. Vokurka, N. J. Oldershaw, Marcello Mannelli, F. Wäckerle, R. Howard, J. S. White, J. G. Layter, I. Trigger, D. R. Ward, T. Kress, G. A. Snow, S. Yamashita, P. Igo-Kemenes, K. Ishii, C. P. Ward, Norbert Wermes, Sherry Towers, T. Kawamoto, Silvia Arcelli, W. R. Gibson, B. T. Bouwens, A. Joly, A. M. Rossi, T. Tsukamoto, M. Kolrep, Jean-Arcady Meyer, Gideon Bella, H. J. Burckhart, Jacqueline Batley, P. Berlich, S. Orito, M. Rosvick, R. M. Brown, Lorne Levinson, R. Bartoldus, J. J. Ward, P. Vikas, D. Lanske, R. Lahmann, R. E. Hughes-Jones, S. B. Anderson, P. Szymanski, S. W. O'Neale, S. Söldner-Rembold, A. Skillman, G. Azuelos, M. Hapke, P. Pfeifenschneider, K. Nagai, D. C. Imrie, T. Omori, N. I. Geddes, T. Behnke, Michael Hildreth, D. E. Hutchcroft, D. R. Rust, P. Scharff-Hansen, H. O. Ogren, Christoph Geich-Gimbel, D. M. Strom, N. L. Rodning, O. Schaile, C. R. Jones, D. L. Rees, G. P. Siroli, B. Poli, M. J. Oreglia, T. P. Kokott, E. do Couto e Silva, A. M. Lee, R. Rylko, M. F. Turner-Watson, M. Morii, Stan Bentvelsen, F. Scharf, E. von Törne, J. Patt, German Martinez, A. M. Smith, M. Gruwé, C. M. Hawkes, Sven Menke, H. M. Fischer, Peter R Hobson, M. Fierro, J. E.G. Edwards, K. Sachs, Paul Kyberd, F. K. Loebinger, P. Routenburg, D. Chrisman, Andris Skuja, J. E. Conboy, Shlomo Dado, J. Steuerer, E. A. Mckigney, J. R. Carter, A. Fürtjes, Hans-Christian Schultz-Coulon, G. N. Patrick, S. Petzold, Matthias Schröder, U. Ruppel, M. R. Ingram, Randall Sobie, Michael Schulz, G. D. Lafferty, G. D. Long, Tetsuro Mashimo, Volker Blobel, Joleen Pater, S. Robertson, S. R. Lautenschlager, H. A. Neal, Gregor Herten, W. P. Lai, M. Thiergen, G. G. Hanson, R. Giacomelli, Richard Nisius, KJ Anderson, T. Hilse, S. A. Robins, W. Gorn, B. Wilkens, O. Runolfsson, J. Lauber, Paolo Giacomelli, P. S. Wells, Marco Cuffiani, M. Hansroul, Giora Mikenberg, John Allison, G. Giacomelli, J. M. Roney, Guenter Duckeck, Terry Richard Wyatt, C. Beeston, B. Stockhausen, Claudio Grandi, C. Burgard, J. E. Bloomer, D. M. Gingrich, J. E. Pilcher, R. G. Kellogg, M. Steiert, Gunter Wolf, Stephen Lloyd, R. J. Homer, Csaba Hajdu, P. Schenk, K. Ackerstaff, Stefano Marcellini, Stefan Schmitt, M. S. Dixit, Frans Meijers, P. G. Estabrooks, R. K. Keeler, Achim Stahl, P. E.L. Clarke, M. K. Jones, P. M. Watkins, J. P. Martin, O. C. Cooke, F. Strumia, S. D. Talbot, U. Müller, S. De Jong, A. J. Martin, P. Mättig, P. Poffenberger, Shoji Asai, J. von Krogh, H. Przysiezniak, P. Schütz, J. Bechtluft, I. J. Bloodworth, K. Ametewee, A. N. Bell, R. J. Hawkings, Gideon Alexander, Paolo Capiluppi, A. I. McNab, M. Schumacher, H. Jeremie, P. Gagnon, Yoram Rozen, E. Lefebvre, L. A. del Pozo, M. Foucher, Ehud Duchovni, J. Goldberg, F. Odorici, C. K. Hargrove, C. Sbarra, Tara Shears, A. Sittler, M. Jimack, D. Karlen, P. A. Hart, B. Nellen, A. Michelini, M. J. Pearce, H. M. Bosch, Satoshi Tanaka, T. Kobayashi, G. Yekutieli, D. Axen, A. Jawahery, A. A. Carter, Daniel Lellouch, H. G. Evans, Peter Sherwood, Ron Folman, Roger Jones, Alexander Wagner, Takehiko Mori, M. J. Goodrick, I. Cohen, J. Ludwig, K. Runge, V. Zacek, P. Bock, B. J. King, P. Utzat, Stefan Kluth, Shlomit Tarem, T. J. McMahon, R. K. Carnegie, M. Herndon, M. Bobinski, J. A. Wilson, and D. Lazic
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Missing energy, Muon, Luminosity (scattering theory), Electron–positron annihilation, High Energy Physics::Phenomenology, Fermion, Standard Model, Nuclear physics, Higgs boson, High Energy Physics::Experiment, Lepton
Abstract: This letter describes a search for the Standard Model Higgs boson using data from e + e − collisions collected at a centre-of-mass energy of 161 GeV by the OPAL detector at LEP. The ata correspond to an integrated luminosity of 10.0 pb −1 . The search is sensitive to the main final states from the process where the Higgs boson is produced in association with a fermion anti-fermion pair, namely four jets, two jets with missing energy, and two jets produced together with a pair of electrons, muons or tau leptons. Two candidate events are observed, in agreement with Standard Model background expectations. In combination with previous OPAL searches at centre-of-mass energies close to the Z 0 resonance, we derive a lower limit of 65.0 GeV for the mass of the Standard Model Higgs boson, at the 95% confidence level.
Published: 1997
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34. QCD studies with e+e- annihilation data at 172-189 GeV

Author: Abbiendi, G., Ackerstaff, K., Akesson, P.F., Alexander, G., Allison, John, Anderson, K.J., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Bailey, I., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Cammin, J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Gunther, P.O., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauke, A., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Hensel, C., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karapetian, G., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klein, K., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kupper, M., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lawson, I., Layter, J.G., Leins, A., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tarem, S., Taylor, R.J., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wengler, T., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., Zer-Zion, D., G., Abbiendi, K., Ackerstaff, P. F., Akesson, G., Alexander, J., Allison, K. J., Anderson, S., Arcelli, S., Asai, S. F., Ashby, D., Axen, G., Azuelo, I., Bailey, A. H., Ball, E., Barberio, R. J., Barlow, J. R., Batley, S., Baumann, T., Behnke, K. W., Bell, G., Bella, A., Bellerive, S., Bentvelsen, S., Bethke, O., Biebel, A., Biguzzi, I. J., Bloodworth, P., Bock, J., Bohme, O., Boeriu, D., Bonacrosi, M., Boutemeur, S., Braibant, P., Bright Thoma, L., Brigliadori, R. M., Brown, H. J., Burckhart, J., Cammin, P., Capiluppi, R. K., Carnegie, A. A., Carter, J. R., Carter, C. Y., Chang, D. G., Charlton, D., Chrisman, C., Ciocca, P. E., L., E., Clay, I., Cohen, O. C., Cooke, J., Couchman, C., Couyoumtzeli, R. L., Coxe, M., Cuffiani, S., Dado, G. M., Dallavalle, S., Dallison, R., Davi, A., de Roeck, P., Dervan, K., Desch, B., Diene, M. S., Dixit, M., Donker, J., Dubbert, E., Duchovni, G., Duckeck, I. P., Duerdoth, P. G., Estabrook, E., Etzion, F., Fabbri, A., Fanfani, M., Fanti, A. A., Faust, L., Feld, P., Ferrari, F., Fiedler, M., Fierro, I., Fleck, A., Frey, A., Furtje, D. I., Futyan, P., Gagnon, J. W., Gary, G., Gaycken, C., Geich Gimbel, G., Giacomelli, P., Giacomelli, D. M., Gingrich, D., Glenzinski, J., Goldberg, W., Gorn, C., Grandi, K., Graham, E., Gro, J., Grunhau, M., Gruwe, P. O., Gunther, C., Hajdu, G. G., Hanson, M., Hansroul, M., Hapke, K., Harder, A., Harel, C. K., Hargrove, M., Harin Dirac, A., Hauke, M., Hauschild, C. M., Hawke, R., Hawking, R. J., Hemingway, C., Hensel, G., Herten, R. D., Heuer, M. D., Hildreth, J. C., Hill, P. R., Hobson, A., Hocker, K., Hoffman, R. J., Homer, A. K., Honma, D., Horvath, K. R., Hossain, R., Howard, P., Huntemeyer, P., Igo Kemene, D. C., Imrie, K., Ishii, F. R., Jacob, A., Jawahery, H., Jeremie, M., Jimack, C. R., Jone, P., Jovanovic, T. R., Junk, N., Kanaya, J., Kanzaki, G., Karapetian, D., Karlen, V., Kartvelishvili, K., Kawagoe, T., Kawamoto, P. I., Kayal, R. K., Keeler, R. G., Kellogg, B. W., Kennedy, D. H., Kim, K., Klein, A., Klier, T., Kobayashi, M., Kobel, T. P., Kokott, M., Kolrep, S., Komamiya, R. V., Kowalewski, T., Kre, P., Krieger, J., von Krogh, T., Kuhl, M., Kupper, P., Kyberd, G. D., Lafferty, H., Landsman, D., Lanske, I., Lawson, J. G., Layter, A., Lein, D., Lellouch, J., Lett, L., Levinson, R., Liebisch, J., Lillich, B., List, C., Littlewood, A. W., Lloyd, S. L., Lloyd, F. K., Loebinger, G. D., Long, M. J., Losty, J., Lu, J., Ludwig, A., Macchiolo, A., Macpherson, W., Mader, M., Mannelli, S., Marcellini, T. E., Marchant, A. J., Martin, J. P., Martin, G., Martinez, T., Mashimo, P., Mattig, W. J., Mcdonald, J., Mckenna, T. J., Mcmahon, R. A., Mcpherson, F., Meijer, P., Mendez Lorenzo, F. S., Merritt, H., Me, I., Meyer, A., Michelini, S., Mihara, G., Mikenberg, D. J., Miller, W., Mohr, A., Montanari, T., Mori, K., Nagai, I., Nakamura, H. A., Neal, R., Nisiu, S. W., O'Neale, F. G., Oakham, F., Odorici, H. O., Ogren, A., Okpara, M. J., Oreglia, S., Orito, G., Pasztor, J. R., Pater, G. N., Patrick, J., Patt, R., Perez Ochoa, P., Pfeifenschneider, J. E., Pilcher, J., Pinfold, D. E., Plane, B., Poli, J., Polok, M., Przybycien, A., Quadt, C., Rembser, H., Rick, S. A., Robin, N., Rodning, J. M., Roney, S., Rosati, K., Roscoe, A. M., Rossi, Y., Rozen, K., Runge, O., Runolfsson, D. R., Rust, K., Sach, T., Saeki, O., Sahr, W. M., Sang, E. K., G., C., Sbarra, A. D., Schaile, O., Schaile, P., Scharff Hansen, S., Schmitt, A., Schoning, M., Schroder, M., Schumacher, C., Schwick, W. G., Scott, R., Seuster, T. G., Shear, B. C., Shen, C. H., Shepherd Themistocleou, P., Sherwood, G. P., Siroli, A., Skuja, A. M., Smith, G. A., Snow, R., Sobie, S., Soldner Rembold, Spagnolo, Stefania Antonia, M., Sproston, A., Stahl, K., Stephen, K., Stoll, D., Strom, R., Strohmer, B., Surrow, S. D., Talbot, S., Tarem, R. J., Taylor, R., Teuscher, M., Thiergen, J., Thoma, M. A., Thomson, E., Torrence, S., Tower, T., Trefzger, I., Trigger, Z., Trocsanyi, E., Tsur, M. F., Turner Watson, I., Ueda, R., Van Kooten, P., Vannerem, M., Verzocchi, H., Vo, D., Waller, C. P., Ward, D. R., Ward, P. M., Watkin, A. T., Watson, N. K., Watson, P. S., Well, T., Wengler, N., Werme, D., Wetterling, J. S., White, G. W., Wilson, J. A., Wilson, T. R., Wyatt, S., Yamashita, V., Zacek, and D., Zer Zion
Subjects: Quantum chromodynamics, Physics, Particle physics, Annihilation, Physics and Astronomy (miscellaneous), 010308 nuclear & particles physics, Hadron, Monte Carlo method, FOS: Physical sciences, 01 natural sciences, Charged particle, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, Strong coupling, High Energy Physics::Experiment, Multiplicity (chemistry), 010306 general physics, Engineering (miscellaneous), Particle Physics - Experiment
Abstract: We have studied hadronic events from e+e- annihilation data at centre-of-mass energies of sqrt{s}=172, 183 and 189 GeV. The total integrated luminosity of the three samples, measured with the OPAL detector, corresponds to 250 pb^-1. We present distributions of event shape variables, charged particle multiplicity and momentum, measured separately in the three data samples. From these we extract measurements of the strong coupling alpha_s, the mean charged particle multiplicity and the peak position xi_0 in the xi_p=ln(1/x_p) distribution. In general the data are described well by analytic QCD calculations and Monte Carlo models. Our measured values of alpha_s, and xi_0 are consistent with previous determinations at sqrt{s}=MZ., Comment: 49 pages, 13 figures, submitted to Eur. Phys. J. C
Published: 2000

35. QCD Analyses and determinations of alpha-s in e+e- Annihilation at energies between 35 and 189 GeV

Author: P. Pfeifenschneider, O. Biebel, P. A. MovillaFernandez, G. Abbiendi, K. Ackerstaff, P. F. Akesson, G. Alexander, J. Allison, K. J. Anderson, S. Arcelli, S. Asai, S. F. Ashby, D. Axen, G. Azuelos, I. Bailey, A. H. Ball, E. Barberio, R. J. Barlow, J. R. Batley, S. Baumann, T. Behnke, K. W. Bell, G. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, A. Biguzzi, I. J. Bloodworth, P. Bock, J. Bohme, O. Boeriu, D. Bonacorsi, M. Boutemeur, S. Braibant, P. Bright Thomas, L. Brigliadori, R. M. Brown, H. J. Burckhart, J. Cammin, P. Capiluppi, R. K. Carnegie, A. A. Carter, J. R. Carter, C. Y. Chang, D. G. Charlton, D. Chrisman, C. Ciocca, P. E. L., E. Clay, I. Cohen, O. C. Cooke, J. Couchman, C. Couyoumtzelis, R. L. Coxe, M. Cuffiani, S. Dado, G. M. Dallavalle, S. Dallison, R. Davis, A. de Roeck, P. Dervan, K. Desch, B. Dienes, M. S. Dixit, M. Donkers, J. Dubbert, E. Duchovni, G. Duckeck, I. P. Duerdoth, P. G. Estabrooks, E. Etzion, F. Fabbri, A. Fanfani, M. Fanti, A. A. Faust, L. Feld, P. Ferrari, F. Fiedler, M. Fierro, I. Fleck, A. Frey, A. Furtjes, D. I. Futyan, P. Gagnon, J. W. Gary, G. Gaycken, C. Geich Gimbel, G. Giacomelli, P. Giacomelli, D. M. Gingrich, D. Glenzinski, J. Goldberg, M. Gorn, C. Grandi, K. Graham, E. Gross, J. Grunhaus, M. Gruwe, P. O. Gunther, C. Hajdu, G. G. Hanson, M. Hansroul, M. Hapke, K. Harder, A. Harel, C. K. Hargrove, M. Harin Dirac, A. Hauke, M. Hauschild, C. M. Hawkes, R. Hawkings, R. J. Hemingway, C. Hensel, G. Herten, R. D. Heuer, M. D. Hildreth, J. C. Hill, P. R. Hobson, A. Hocker, K. Hoffman, R. J. Homer, A. K. Honma, D. Horvath, K. R. Hossain, R. Howard, P. Huntemeyer, P. Igo Kemenes, D. C. Imrie, K. Ishii, F. R. Jacob, A. Jawahery, H. Jeremie, M. Jimack, C. R. Jones, P. Jovanovic, T. R. Junk, N. Kanaya, J. Kanzaki, G. Karapetian, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P. I. Kayal, R. K. Keeler, R. G. Kellogg, B. W. Kennedy, D. H. Kim, A. Klier, T. Kobayashi, M. Kobel, T. P. Kokott, M. Kolrep, S. Komamiya, R. V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, T. Kuhl, M. Kupper, P. Kyberd, G. D. Lafferty, H. Landsman, D. Lanske, I. Lawson, J. G. Layter, A. Leins, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, J. Lillich, B. List, C. Littlewood, A. W. Lloyd, S. L. Lloyd, F. K. Loebinger, G. D. Long, M. J. Losty, J. Lu, J. Ludwig, A. Macchiolo, A. Macpherson, W. Mader, M. Mannelli, S. Marcellini, T. E. Marchant, A. J. Martin, J. P. Martin, G. Martinez, T. Mashimo, P. Mattig, W. J. McDonald, J. McKenna, T. J. McMahon, R. A. McPherson, F. Meijers, P. Mendez Lorenzo, F. S. Merritt, H. Mes, I. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D. J. Miller, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H. A. Neal, R. Nisius, S. W. O'Neale, F. G. Oakham, F. Odorici, H. O. Ogren, A. Okpara, M. J. Oreglia, S. Orito, G. Pasztor, J. R. Pater, G. N. Patrick, J. Patt, R. Perez Ochoa, J. E. Pilcher, J. Pinfold, D. E. Plane, B. Poli, J. Polok, M. Przybycien, A. Quadt, C. Rembser, H. Rick, S. A. Robins, N. Rodning, J. M. Roney, S. Rosati, K. Roscoe, A. M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D. R. Rust, K. Sachs, T. Saeki, O. Sahr, W. M. Sang, E. K. G., C. Sbarra, A. D. Schaile, O. Schaile, P. Scharff Hansen, J. Schieck, S. Schmitt, A. Schoning, M. Schroder, M. Schumacher, C. Schwick, W. G. Scott, R. Seuster, T. G. Shears, B. C. Shen, C. H. Shepherd Themistocleous, P. Sherwood, G. P. Siroli, A. Skuja, A. M. Smith, G. A. Snow, R. Sobie, S. Soldner Rembold, M. Sproston, A. Stahl, K. Stephens, K. Stoll, D. Strom, R. Strohmer, B. Surrow, S. D. Talbot, S. Tarem, R. J. Taylor, R. Teuscher, M. Thiergen, J. Thomas, M. A. Thomson, E. Torrence, S. Towers, T. Trefzger, I. Trigger, Z. Trocsanyi, E. Tsur, M. F. Turner Watson, I. Ueda, R. Van Kooten, P. Vannerem, M. Verzocchi, H. Voss, D. Waller, C. P. Ward, D. R. Ward, P. M. Watkins, A. T. Watson, N. K. Watson, P. S. Wells, T. Wengler, N. Wermes, D. Wetterling, J. S. White, G. W. Willson, J. A. Wilson, T. R. Wyatt, S. Yamashita, V. Zacek, D. Zer Zion, SPAGNOLO, Stefania Antonia, P., Pfeifenschneider, O., Biebel, P. A., Movillafernandez, G., Abbiendi, K., Ackerstaff, P. F., Akesson, G., Alexander, J., Allison, K. J., Anderson, S., Arcelli, S., Asai, S. F., Ashby, D., Axen, G., Azuelo, I., Bailey, A. H., Ball, E., Barberio, R. J., Barlow, J. R., Batley, S., Baumann, T., Behnke, K. W., Bell, G., Bella, A., Bellerive, S., Bentvelsen, S., Bethke, A., Biguzzi, I. J., Bloodworth, P., Bock, J., Bohme, O., Boeriu, D., Bonacorsi, M., Boutemeur, S., Braibant, P., Bright Thoma, L., Brigliadori, R. M., Brown, H. J., Burckhart, J., Cammin, P., Capiluppi, R. K., Carnegie, A. A., Carter, J. R., Carter, C. Y., Chang, D. G., Charlton, D., Chrisman, C., Ciocca, P. E., L., E., Clay, I., Cohen, O. C., Cooke, J., Couchman, C., Couyoumtzeli, R. L., Coxe, M., Cuffiani, S., Dado, G. M., Dallavalle, S., Dallison, R., Davi, A., de Roeck, P., Dervan, K., Desch, B., Diene, M. S., Dixit, M., Donker, J., Dubbert, E., Duchovni, G., Duckeck, I. P., Duerdoth, P. G., Estabrook, E., Etzion, F., Fabbri, A., Fanfani, M., Fanti, A. A., Faust, L., Feld, P., Ferrari, F., Fiedler, M., Fierro, I., Fleck, A., Frey, A., Furtje, D. I., Futyan, P., Gagnon, J. W., Gary, G., Gaycken, C., Geich Gimbel, G., Giacomelli, P., Giacomelli, D. M., Gingrich, D., Glenzinski, J., Goldberg, M., Gorn, C., Grandi, K., Graham, E., Gro, J., Grunhau, M., Gruwe, P. O., Gunther, C., Hajdu, G. G., Hanson, M., Hansroul, M., Hapke, K., Harder, A., Harel, C. K., Hargrove, M., Harin Dirac, A., Hauke, M., Hauschild, C. M., Hawke, R., Hawking, R. J., Hemingway, C., Hensel, G., Herten, R. D., Heuer, M. D., Hildreth, J. C., Hill, P. R., Hobson, A., Hocker, K., Hoffman, R. J., Homer, A. K., Honma, D., Horvath, K. R., Hossain, R., Howard, P., Huntemeyer, P., Igo Kemene, D. C., Imrie, K., Ishii, F. R., Jacob, A., Jawahery, H., Jeremie, M., Jimack, C. R., Jone, P., Jovanovic, T. R., Junk, N., Kanaya, J., Kanzaki, G., Karapetian, D., Karlen, V., Kartvelishvili, K., Kawagoe, T., Kawamoto, P. I., Kayal, R. K., Keeler, R. G., Kellogg, B. W., Kennedy, D. H., Kim, A., Klier, T., Kobayashi, M., Kobel, T. P., Kokott, M., Kolrep, S., Komamiya, R. V., Kowalewski, T., Kre, P., Krieger, J., von Krogh, T., Kuhl, M., Kupper, P., Kyberd, G. D., Lafferty, H., Landsman, D., Lanske, I., Lawson, J. G., Layter, A., Lein, D., Lellouch, J., Lett, L., Levinson, R., Liebisch, J., Lillich, B., List, C., Littlewood, A. W., Lloyd, S. L., Lloyd, F. K., Loebinger, G. D., Long, M. J., Losty, J., Lu, J., Ludwig, A., Macchiolo, A., Macpherson, W., Mader, M., Mannelli, S., Marcellini, T. E., Marchant, A. J., Martin, J. P., Martin, G., Martinez, T., Mashimo, P., Mattig, W. J., Mcdonald, J., Mckenna, T. J., Mcmahon, R. A., Mcpherson, F., Meijer, P., Mendez Lorenzo, F. S., Merritt, H., Me, I., Meyer, A., Michelini, S., Mihara, G., Mikenberg, D. J., Miller, W., Mohr, A., Montanari, T., Mori, K., Nagai, I., Nakamura, H. A., Neal, R., Nisiu, S. W., O'Neale, F. G., Oakham, F., Odorici, H. O., Ogren, A., Okpara, M. J., Oreglia, S., Orito, G., Pasztor, J. R., Pater, G. N., Patrick, J., Patt, R., Perez Ochoa, J. E., Pilcher, J., Pinfold, D. E., Plane, B., Poli, J., Polok, M., Przybycien, A., Quadt, C., Rembser, H., Rick, S. A., Robin, N., Rodning, J. M., Roney, S., Rosati, K., Roscoe, A. M., Rossi, Y., Rozen, K., Runge, O., Runolfsson, D. R., Rust, K., Sach, T., Saeki, O., Sahr, W. M., Sang, E. K., G., C., Sbarra, A. D., Schaile, O., Schaile, P., Scharff Hansen, J., Schieck, S., Schmitt, A., Schoning, M., Schroder, M., Schumacher, C., Schwick, W. G., Scott, R., Seuster, T. G., Shear, B. C., Shen, C. H., Shepherd Themistocleou, P., Sherwood, G. P., Siroli, A., Skuja, A. M., Smith, G. A., Snow, R., Sobie, S., Soldner Rembold, Spagnolo, Stefania Antonia, M., Sproston, A., Stahl, K., Stephen, K., Stoll, D., Strom, R., Strohmer, B., Surrow, S. D., Talbot, S., Tarem, R. J., Taylor, R., Teuscher, M., Thiergen, J., Thoma, M. A., Thomson, E., Torrence, S., Tower, T., Trefzger, I., Trigger, Z., Trocsanyi, E., Tsur, M. F., Turner Watson, I., Ueda, R., Van Kooten, P., Vannerem, M., Verzocchi, H., Vo, D., Waller, C. P., Ward, D. R., Ward, P. M., Watkin, A. T., Watson, N. K., Watson, P. S., Well, T., Wengler, N., Werme, D., Wetterling, J. S., White, G. W., Willson, J. A., Wilson, T. R., Wyatt, S., Yamashita, V., Zacek, and D., Zer Zion
Subjects: Quantum chromodynamics, Physics, Particle physics, Annihilation, Physics and Astronomy (miscellaneous), 010308 nuclear & particles physics, Hadron, Monte Carlo method, High Energy Physics::Phenomenology, FOS: Physical sciences, Jet (particle physics), 01 natural sciences, JADE (particle detector), High Energy Physics - Experiment, Renormalization, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Engineering (miscellaneous), Energy (signal processing), Particle Physics - Experiment
Abstract: We employ data taken by the JADE and OPAL experiments for an integrated QCD study in hadronic e+e- annihilations at c.m.s. energies ranging from 35 GeV through 189 GeV. The study is based on jet-multiplicity related observables. The observables are obtained to high jet resolution scales with the JADE, Durham, Cambridge and cone jet finders, and compared with the predictions of various QCD and Monte Carlo models. The strong coupling strength, alpha_s, is determined at each energy by fits of O(alpha_s^2) calculations, as well as matched O(alpha_s^2) and NLLA predictions, to the data. Matching schemes are compared, and the dependence of the results on the choice of the renormalization scale is investigated. The combination of the results using matched predictions gives alpha_s(MZ)=0.1187+{0.0034}-{0.0019}. The strong coupling is also obtained, at lower precision, from O(alpha_s^2) fits of the c.m.s. energy evolution of some of the observables. A qualitative comparison is made between the data and a recent MLLA prediction for mean jet multiplicities., 49 pages, 17 figures, submitted to Eur.Phys.J. C
Published: 2000

36. Precision Luminosity for Z0 Lineshape Measurements with a Silicon-Tungsten Calorimeter

Author: Abbiendi, G, Ackerstaff, K, Alexander, G, Allison, J, Anderson, KJ, Anderson, S, Arcelli, S, Asai, S, Ashby, SF, Axen, D, Azuelos, G, Graham, K, Gross, E, Grunhaus, J, Gruwe, M, Hajdu, C, Hanson, GG, Hansroul, M, Hapke, M, Harder, K, Harel, A, Ball, AH, Hargrove, CK, Harin-Dirac, M, Hart, P, Hauschild, M, Hawkes, CM, Hawkings, R, Hemingway, RJ, Herten, G, Heuer, RD, Hildreth, MD, Barberio, E, Hill, JC, Hillier, S, Hobson, PR, Hocker, A, Hoffman, K, Homer, RJ, Honma, AK, Horvath, D, Hossain, KR, Howard, R, Barlow, RJ, Huntemeyer, P, Igo-Kemenes, P, Imrie, DC, Ishii, K, Jacob, FR, Jawahery, A, Jeremie, H, Jimack, M, Jones, CR, Jovanovic, P, Batley, JR, Junk, TR, Kanaya, N, Kanzaki, J, Karlen, D, Kartvelishvili, V, Kawagoe, K, Kawamoto, T, Kayal, PI, Keeler, RK, Kellogg, RG, Baumann, S, Kennedy, BW, Kim, DH, Kirk, J, Klier, A, Kobayashi, T, Kobel, M, Kokott, TP, Kolrep, M, Komamiya, S, Kowalewski, RV, Bechtluft, J, Kress, T, Krieger, P, von Krogh, J, Kuhl, T, Kyberd, P, Lai, WP, Lafferty, GD, Lahmann, R, Landsman, H, Lanske, D, Behnke, T, Lauber, J, Lawson, I, Layter, JG, Lee, AM, Lellouch, D, Letts, J, Levinson, L, Liebisch, R, Lillich, J, List, B, Bell, KW, Littlewood, C, Lloyd, AW, Lloyd, SL, Loebinger, FK, Long, GD, Losty, MJ, Lu, J, Ludwig, J, Liu, D, Macchiolo, A, Bella, G, Macpherson, A, Mader, W, Mannelli, M, Marcellini, S, Marchant, TE, Martin, AJ, Martin, JP, Martinez, G, Mashimo, T, Mattig, P, Bellerive, A, McDonald, WJ, McKenna, J, Mckigney, EA, McMahon, TJ, McPherson, RA, Meijers, F, Mendez-Lorenzo, P, Menke, S, Merritt, FS, Mes, H, Bentvelsen, S, Meyer, I, Michelini, A, Mihara, S, Mikenberg, G, Miller, DJ, Mohr, W, Montanari, A, Mori, T, Muller, U, Nagai, K, Bethke, S, Nakamura, I, Neal, HA, Nisius, R, O'Neale, SW, Oakham, FG, Odorici, F, Ogren, HO, Okpara, A, Oreglia, MJ, Orito, S, Betts, S, Palmonari, F, Pasztor, G, Pater, JR, Patrick, GN, Patt, J, Perez-Ochoa, R, Petzold, S, Pfeifenschneider, P, Pilcher, JE, Pinfold, J, Biebel, O, Plane, DE, Poffenberger, P, Poli, B, Polok, J, Przybycien, M, Quadt, A, Raith, B, Rembser, C, Rick, H, Robertson, S, Biguzzi, A, Robins, SA, Rodning, N, Roney, JM, Rosati, S, Roscoe, K, Rossi, AM, Rozen, Y, Runge, K, Runolfsson, O, Rust, DR, Bloodworth, IJ, Sachs, K, Saeki, T, Sahr, O, Sang, WM, Sarkisyan, EKG, Sbarra, C, Schaile, AD, Schaile, O, Scharff-Hansen, P, Schieck, J, Bock, P, Schmitt, B, Schmitt, S, Schoning, A, Schroder, M, Schumacher, M, Schwick, C, Scott, WG, Seuster, R, Shears, TG, Shen, BC, Bohme, J, Shepherd-Themistocleous, CH, Sherwood, P, Siroli, GP, Skuja, A, Smith, AM, Snow, GA, Sobie, R, Soldner-Rembold, S, Spagnolo, S, Springer, W, Boeriu, O, Sproston, M, Stahl, A, Stephens, K, Stoll, K, Strom, D, Strohmer, R, Surrow, B, Talbot, SD, Taras, P, Tarem, S, Bonacorsi, D, Tecchio, M, Teuscher, R, Thiergen, M, Thomas, J, Thomson, MA, Torrence, E, Towers, S, Trefzger, T, Trigger, I, Trocsanyi, Z, Boutemeur, M, Tsur, E, Turner-Watson, MF, Ueda, I, Van Kooten, R, Vannerem, P, Verzocchi, M, Voss, H, Wackerle, F, Wagner, A, Wagner, D, Braibant, S, Waller, D, Ward, CP, Ward, DR, Watkins, PM, Watson, AT, Watson, NK, Wells, PS, Wermes, N, Wetterling, D, White, JS, Bright-Thomas, P, Wilson, GW, Wilson, JA, Wyatt, TR, Yamashita, S, Zacek, V, Zer-Zion, D, OPAL Collaboration, Brigliadori, L, Brown, RM, Burckhart, HJ, Capiluppi, P, Carnegie, RK, Carter, AA, Carter, JR, Chang, CY, Charlton, DG, Chrisman, D, Ciocca, C, Clarke, PEL, Clay, E, Cohen, I, Conboy, JE, Cooke, OC, Couchman, J, Couyoumtzelis, C, Coxe, RL, Cuffiani, M, Dado, S, Dallavalle, GM, Dallison, S, Darling, C, Davis, R, De Jong, S, de Roeck, A, Dervan, P, Desch, K, Dienes, B, Dixit, MS, Donkers, M, Dubbert, J, Duchovni, E, Duckeck, G, Duerdoth, IP, Estabrooks, PG, Etzion, E, Evans, H, Fabbri, F, Fanfani, A, Fanti, M, Faust, AA, Feld, L, Ferrari, P, Fiedler, F, Fierro, M, Fleck, I, Foucher, M, Frey, A, Furtjes, A, Futyan, DI, Gagnon, P, Gary, JW, Gascon-Shotkin, S, Gaycken, G, Geich-Gimbel, C, Giacomelli, G, Giacomelli, P, Giacomelli, R, Gibson, WR, Gingrich, DM, Glenzinski, D, Goldberg, J, Gorn, W, Grandi, C, G., Abbiendi, K., Ackerstaff, G., Alexander, J., Allison, K. J., Anderson, S., Anderson, S., Arcelli, S., Asai, S. F., Ashby, D., Axen, G., Azuelo, A. H., Ball, E., Barberio, R. J., Barlow, J. R., Batley, S., Baumann, J., Bechtluft, T., Behnke, K. W., Bell, G., Bella, A., Bellerive, S., Bentvelsen, S., Bethke, S., Bett, O., Biebel, A., Biguzzi, I. J., Bloodworth, P., Bock, J., Bohme, O., Boeriu, D., Bonacorsi, M., Boutemeur, S., Braibant, P., Bright Thoma, L., Brigliadori, R. M., Brown, H. J., Burckhart, P., Capiluppi, R. K., Carnegie, A. A., Carter, J. R., Carter, C. Y., Chang, D. G., Charlton, D., Chrisman, C., Ciocca, P. E., L., E., Clay, I., Cohen, J. E., Conboy, O. C., Cooke, J., Couchman, C., Couyoumtzeli, R. L., Coxe, M., Cuffiani, S., Dado, G. M., Dallavalle, S., Dallison, C., Darling, R., Davi, S., De Jong, A., de Roeck, P., Dervan, K., Desch, B., Diene, M. S., Dixit, M., Donker, J., Dubbert, E., Duchovni, G., Duckeck, I. P., Duerdoth, P. G., Estabrook, E., Etzion, H., Evan, F., Fabbri, A., Fanfani, M., Fanti, A. A., Faust, L., Feld, P., Ferrari, F., Fiedler, M., Fierro, I., Fleck, M., Foucher, A., Frey, A., Furtje, D. I., Futyan, P., Gagnon, J. W., Gary, S., Gascon Shotkin, G., Gaycken, C., Geich Gimbel, G., Giacomelli, P., Giacomelli, R., Giacomelli, W. R., Gibson, D. M., Gingrich, D., Glenzinski, J., Goldberg, W., Gorn, C., Grandi, K., Graham, E., Gro, J., Grunhau, M., Gruwe, C., Hajdu, G. G., Hanson, M., Hansroul, M., Hapke, K., Harder, A., Harel, C. K., Hargrove, M., Harin Dirac, P., Hart, M., Hauschild, C. M., Hawke, R., Hawking, R. J., Hemingway, G., Herten, R. D., Heuer, M. D., Hildreth, J. C., Hill, S., Hillier, P. R., Hobson, A., Hocker, K., Hoffman, R. J., Homer, A. K., Honma, D., Horvath, K. R., Hossain, R., Howard, P., Huntemeyer, P., Igo Kemene, D. C., Imrie, K., Ishii, F. R., Jacob, A., Jawahery, H., Jeremie, M., Jimack, C. R., Jone, P., Jovanovic, T. R., Junk, N., Kanaya, J., Kanzaki, D., Karlen, V., Kartvelishvili, K., Kawagoe, T., Kawamoto, P. I., Kayal, R. K., Keeler, R. G., Kellogg, B. W., Kennedy, D. H., Kim, J., Kirk, A., Klier, T., Kobayashi, M., Kobel, T. P., Kokott, M., Kolrep, S., Komamiya, R. V., Kowalewski, T., Kre, P., Krieger, J., von Krogh, T., Kuhl, P., Kyberd, W. P., Lai, G. D., Lafferty, R., Lahmann, H., Landsman, D., Lanske, J., Lauber, I., Lawson, J. G., Layter, A. M., Lee, D., Lellouch, J., Lett, L., Levinson, R., Liebisch, J., Lillich, B., List, C., Littlewood, A. W., Lloyd, S. L., Lloyd, F. K., Loebinger, G. D., Long, M. J., Losty, J., Lu, J., Ludwig, D., Liu, A., Macchiolo, A., Macpherson, W., Mader, M., Mannelli, S., Marcellini, T. E., Marchant, A. J., Martin, J. P., Martin, G., Martinez, T., Mashimo, P., Mattig, W. J., Mcdonald, J., Mckenna, E. A., Mckigney, T. J., Mcmahon, R. A., Mcpherson, F., Meijer, P., Mendez Lorenzo, S., Menke, F. S., Merritt, H., Me, I., Meyer, A., Michelini, S., Mihara, G., Mikenberg, D. J., Miller, W., Mohr, A., Montanari, T., Mori, U., Muller, K., Nagai, I., Nakamura, H. A., Neal, R., Nisiu, S. W., O'Neale, F. G., Oakham, F., Odorici, H. O., Ogren, A., Okpara, M. J., Oreglia, S., Orito, F., Palmonari, G., Pasztor, J. R., Pater, G. N., Patrick, J., Patt, R., Perez Ochoa, S., Petzold, P., Pfeifenschneider, J. E., Pilcher, J., Pinfold, D. E., Plane, P., Poffenberger, B., Poli, J., Polok, M., Przybycien, A., Quadt, B., Raith, C., Rembser, H., Rick, S., Robertson, S. A., Robin, N., Rodning, J. M., Roney, S., Rosati, K., Roscoe, A. M., Rossi, Y., Rozen, K., Runge, O., Runolfsson, D. R., Rust, K., Sach, T., Saeki, O., Sahr, W. M., Sang, E. K., G., C., Sbarra, A. D., Schaile, O., Schaile, P., Scharff Hansen, J., Schieck, B., Schmitt, S., Schmitt, A., Schoning, M., Schroder, M., Schumacher, C., Schwick, W. G., Scott, R., Seuster, T. G., Shear, B. C., Shen, C. H., Shepherd Themistocleou, P., Sherwood, G. P., Siroli, A., Skuja, A. M., Smith, G. A., Snow, R., Sobie, S., Soldner Rembold, Spagnolo, Stefania Antonia, W., Springer, M., Sproston, A., Stahl, K., Stephen, K., Stoll, D., Strom, R., Strohmer, B., Surrow, S. D., Talbot, P., Tara, S., Tarem, M., Tecchio, R., Teuscher, M., Thiergen, J., Thoma, M. A., Thomson, E., Torrence, S., Tower, T., Trefzger, I., Trigger, Z., Trocsanyi, E., Tsur, M. F., Turner Watson, I., Ueda, R., Van Kooten, P., Vannerem, M., Verzocchi, H., Vo, F., Wackerle, A., Wagner, D., Wagner, D., Waller, C. P., Ward, D. R., Ward, P. M., Watkin, A. T., Watson, N. K., Watson, P. S., Well, N., Werme, D., Wetterling, J. S., White, G. W., Wilson, J. A., Wilson, T. R., Wyatt, S., Yamashita, V., Zacek, and D., Zer Zion
Subjects: LOW-NOISE, Particle physics, E+E ANNIHILATION, Photon, Physics and Astronomy (miscellaneous), Physics::Instrumentation and Detectors, FOS: Physical sciences, Electron, INCLUSIVE MUON PRODUCTION, 01 natural sciences, OPAL DETECTOR, Radiation length, High Energy Physics - Experiment, Nuclear physics, BHABHA SCATTERING, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, 010306 general physics, Engineering (miscellaneous), Bhabha scattering, Physics, Luminosity (scattering theory), Interaction point, ELECTROWEAK PARAMETERS, 010308 nuclear & particles physics, CMOS SIGNAL PROCESSOR, MICROVERTEX DETECTOR, SMALL-ANGLE, Calorimeter, TOTAL CROSS-SECTION, High Energy Physics::Experiment, Event (particle physics), Particle Physics - Experiment
Abstract: The measurement of small-angle Bhabha scattering is used to determine the luminosity at the OPAL interaction point for the LEP I data recorded between 1993 and 1995. The measurement is based on the OPAL Silicon-Tungsten Luminometer which is composed of two calorimeters encircling the LEP beam pipe, on opposite sides of the interaction point. The luminometer detects electrons from small-angle Bhabha scattering at angles between 25 and 58mrad. At LEP center-of-mass energies around the Z0, about half of all Bhabha electrons entering the detector fall within a 79nb fiducial acceptance region. The electromagnetic showers generated in the stack of 1 radiation length tungsten absorber plates are sampled by 608 silicon detectors with 38,912 radial pads of 2.5mm width.The fine segmentation of the detector, combined with the precise knowledge of its physical dimensions, allows the trajectories of incoming 45GeV electrons or photons to be determined with a total systematic error of less than 7microns. We have quantified all significant sources of systematic experimental error in the luminosity determination by direct physical measurement. All measured properites of the luminosity event sample are found to be in agreement with current theoretical expectations. The total systematic measurement uncertainty is 3.4x10^-4, significantly below the theoretical error of 5.4x10^-4 currently assigned to the QED calculation of the Bhabha acceptance, and contributes negligibly to the total uncertainty in the OPAL measurement of Gamma{invisible}/Gamma{l+l-}, a quantity of basic physical interest which depends crucially on the luminosity measurement., Comment: 87 pages, 36 figures, submitted to Eur.Phys. J. C. Updated references
Published: 1999
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37. Search for new Physics in rare B Decays

Author: Abbiendi, G., Ackerstaff, K., Akesson, P.F., Alexander, G., Allison, John, Anderson, K.J., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Bailey, I., Ball, A.H., Barberio, E., Barlow, Roger J., Batley, J.R., Baumann, S., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Biebel, O., Biguzzi, A., Bloodworth, I.J., Bock, P., Bohme, J., Boeriu, O., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Cammin, J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Cooke, O.C., Couchman, J., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Dallison, S., Davis, R., de Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Donkers, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanfani, A., Fanti, M., Faust, A.A., Feld, L., Ferrari, P., Fiedler, F., Fierro, M., Fleck, I., Frey, A., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Gunther, P.O., Hajdu, C., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Harin-Dirac, M., Hauke, A., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Hensel, C., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Kanaya, N., Kanzaki, J., Karapetian, G., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klein, K., Klier, A., Kobayashi, T., Kobel, M., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kupper, M., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lawson, I., Layter, J.G., Leins, A., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., Lillich, J., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Lu, J., Ludwig, J., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Marchant, T.E., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., McMahon, T.J., McPherson, R.A., Meijers, F., Mendez-Lorenzo, P., Merritt, F.S., Mes, H., Meyer, I., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Okpara, A., Oreglia, M.J., Orito, S., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poli, B., Polok, J., Przybycien, M., Quadt, A., Rembser, C., Rick, H., Robins, S.A., Rodning, N., Roney, J.M., Rosati, S., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharff-Hansen, P., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tarem, S., Taylor, R.J., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., Torrence, E., Towers, S., Trefzger, T., Trigger, I., Trocsanyi, Z., Tsur, E., Turner-Watson, M.F., Ueda, I., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Waller, D., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wengler, T., Wermes, N., Wetterling, D., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Zacek, V., and Zer-Zion, D.
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, Branching fraction, Physics beyond the Standard Model, FOS: Physical sciences, 01 natural sciences, Standard Model, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, High Energy Physics::Experiment, Limit (mathematics), 010306 general physics, Particle Physics - Experiment
Abstract: A search for the decay B+- to K+-K+-pi-+ was performed using data collected by the OPAL detector at LEP. These decays are strongly suppressed in the Standard Model but could occur with a higher branching ratio in supersymmetric models, especially in those with R-parity violating couplings. No evidence for a signal was observed and a 90% confidence level upper limit of 1.29x10^-4 was set for the branching ratio., Comment: 15 pages, 4 figures, to be published in Phys. Letts. B
Published: 2000
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38. Inclusive production of $D^{*\pm}$ mesons in photon-photon collisions at $\sqrt{s}_{ee}$= 183 and 189 GeV and a first measurement of $F^{\gamma}_{2,c}$

Author: H. Mes, I. P. Duerdoth, S. Braibant, T. R. Junk, P. S. Wells, G. Mikenberg, P. Hüntemeyer, Terry Richard Wyatt, A. T. Watson, Ekg Sarkisyan, T. Kobayashi, P. Igo-Kemenes, Ehud Duchovni, K. Ishii, T. Behnke, H. Jeremie, T. Kuhl, N. K. Watson, Richard Nisius, Matthias Schröder, M. Jimack, O. Schaile, B. List, Erez Etzion, M. Thiergen, A. Michelini, F. Wäckerle, D. M. Gingrich, R. G. Kellogg, Marco Cuffiani, P. E.L. Clarke, G. Gaycken, P. G. Bright-Thomas, Dave Charlton, Shlomit Tarem, J. P. Martin, I. J. Bloodworth, D. Lanske, Stefano Marcellini, C. Y. Chang, A. Macpherson, M. Schumacher, A. M. Rossi, J. Lauber, B. Surrow, P. Taras, Yoram Rozen, P. I. Kayal, S. A. Robins, P. F. Åkesson, F. Odorici, Paul Kyberd, F. K. Loebinger, Ivor Fleck, H. Rick, Achim Stahl, Naoko Kanaya, R. L. Coxe, R. J. Sobie, R. Liebisch, Joleen Pater, A. Klier, R. D. Heuer, A. J. Martin, S. Baumann, Norbert Wermes, A. Hocker, K. Ackerstaff, D. R. Rust, K. Hoffman, Junichi Kanzaki, S. D. Talbot, H. A. Neal, Sherry Towers, Klaus Desch, J. Polok, T. Kawamoto, D. Karlen, Raimund Ströhmer, R. Howard, Thorsten Wengler, A. D. Schaile, D. Chrisman, G. D. Long, Gideon Bella, J. A. McKenna, O. Runolfsson, Gabriella Pasztor, P. Vannerem, P. Scharff-Hansen, M. Fanti, S. Orito, A. Biguzzi, E. A. Mckigney, J. Couchman, W. Mader, S. Betts, A. K. Honma, H. Voss, M. Hapke, J. G. Layter, W. M. Sang, C. K. Hargrove, C. H. Shepherd-Themistocleous, J. Grunhaus, Robert McPherson, K. Graham, G. A. Snow, C. P. Ward, Claudio Grandi, T. Barillari, Tara Shears, H. J. Burckhart, Jacqueline Batley, Stefan Schmitt, Fabrizio Fabbri, Richard Teuscher, Claudia Ciocca, A. Frey, S. Söldner-Rembold, W.J. McDonald, Beatrix Dienes, S. Rosati, D. J. Miller, M. J. Oreglia, O. C. Cooke, A. A. Faust, F. Fiedler, P. Pfeifenschneider, Shoji Asai, G. D. Lafferty, D. I. Futyan, R. Kowalewski, J. R. Carter, F. R. Jacob, S.J. Dallison, J. Letts, S. Arcelli, A. M. Smith, J. Goldberg, P. Gagnon, A. Harel, J. Patt, André Schöning, L. Brigliadori, O. Sahr, Ikuo Ueda, D. M. Strom, J. Allison, G. N. Patrick, Daniel Lellouch, J. Lu, Takehiko Mori, S. Spagnolo, A. W. Lloyd, G. Giacomelli, A. Okpara, R. Hawkings, C. R. Jones, Juergen Thomas, P. Mättig, I. Lawson, Gideon Alexander, Satoshi Mihara, K. Sachs, A. De Roeck, M. Kobel, Paolo Capiluppi, Shlomo Dado, P. G. Estabrooks, R. K. Keeler, Zoltan Laszlo Trocsanyi, Sachio Komamiya, R VanKooten, C. Sbarra, S. W. O'Neale, G. W. Wilson, M. Hauschild, M. S. Dixit, Frans Meijers, H. Landsman, Dong Hee Kim, Michael Hildreth, Alain Bellerive, I. Cohen, R. J. Barlow, Christoph Rembser, M. Verzocchi, Arnulf Quadt, James Pinfold, R. Perez-Ochoa, R. Seuster, Paolo Giacomelli, M. Hansroul, N. L. Rodning, P. Dervan, M. Fierro, P. M. Watkins, M. Kolrep, B. Poli, F. G. Oakham, K. J. Anderson, T. P. Kokott, D. Waller, S. F. Ashby, M. Harin-Dirac, E. L. Barberio, R. J. Homer, K. Stephens, V. Zacek, T. Saeki, Marcello Mannelli, C. Littlewood, R. J. Hemingway, K. Stoll, Andris Skuja, J. Lillich, D. Axen, Alessandra Fanfani, R. Davis, S. Petzold, B. W. Kennedy, P. Jovanovic, Tetsuro Mashimo, M. F. Turner-Watson, A. Jawahery, Austin Ball, Peter Krieger, Oana Elena Vickey Boeriu, Alessandro Montanari, I. Meyer, Peter Sherwood, Stan Bentvelsen, M. Kupper, G. Duckeck, W. Gorn, A. Macchiolo, J. Ludwig, K. Runge, P. Bock, I. Trigger, Thomas E Marchant, D. R. Ward, Peter R Hobson, T. J. McMahon, D. Zer-Zion, C. Couyoumtzelis, M. A. Thomson, J. Dubbert, R. K. Carnegie, E. K. U. Gross, D. E. Plane, Georges Azuelos, M. Sproston, E. Tsur, C. M. Hawkes, K. W. Bell, Kiyotomo Kawagoe, J. C. Hill, B. C. Shen, G. M. Dallavalle, Satoru Yamashita, M. Donkers, J. A. Wilson, Siegfried Bethke, W. G. Scott, I. Nakamura, J. Böhme, J. W. Gary, P. Mendez-Lorenzo, D. Glenzinski, P. Ferrari, Dezso Horvath, M. J. Losty, G. Karapetian, T. Trefzger, K. R. Hossain, K. Roscoe, German Martinez, Daniele Bonacorsi, E. Torrence, E. Clay, J. M. Roney, K. Harder, Koichi Nagai, J. Schieck, R. M. Brown, D. C. Imrie, Lorne Levinson, J. von Krogh, W. Mohr, I. R. Bailey, O. Biebel, G. P. Siroli, Christoph Schwick, M. Gruwé, M. Boutemeur, F. S. Merritt, M. Przybycień, T. Kress, A. A. Carter, Giovanni Abbiendi, H. O. Ogren, Christoph Geich-Gimbel, Vakhtang Kartvelishvili, S. L. Lloyd, J. E. Conboy, A. Fürtjes, Lutz Feld, Gregor Herten, and J. E. Pilcher
Subjects: Physics, Particle physics, Photon, Physics and Astronomy (miscellaneous), Meson, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Perturbative QCD, Order (ring theory), 01 natural sciences, Photon structure function, Charm quark, Nuclear physics, Pseudorapidity, 0103 physical sciences, Production (computer science), High Energy Physics::Experiment, 010306 general physics, Nuclear Experiment, Engineering (miscellaneous), Particle Physics - Experiment
Abstract: The inclusive production of D*+- mesons in photon-photon collisions has been measured using the OPAL detector at LEP at e+e- centre-of-mass energies of 183 and 189GeV. The D* mesons are reconstructed in their decay to D0pi+ with the D0 observed in the two decay modes Kpi+ and Kpi+pi-pi+. After background subtraction, 100.4+-12.6(stat) D*+- mesons have been selected in events without observed scattered beam electron ("anti-tagged") and 29.8+-5.9 (stat) D*+- mesons in events where one beam electron is scattered into the detector ("single-tagged"). Direct and single-resolved events are studied separately. Differential cross-sections as functions of the D* transverse momentum p_t and pseudorapidity \eta are presented in the kinematic region 2
Published: 1999

39. Multi-photon production in e+e− collisions at √s = 189 GeV

Author: M. Schumacher, John Allison, Raimund Ströhmer, F. Odorici, Otmar Biebel, S. Yamashita, K. Hoffman, P. Igo-Kemenes, T. R. Junk, R. G. Kellogg, D. Axen, K. Ishii, H. Jeremie, P. Poffenberger, P. S. Wells, D. J. Miller, Dave Charlton, M. Fierro, I. J. Bloodworth, A. Jawahery, Csaba Hajdu, Oana Elena Vickey Boeriu, O. Runolfsson, S. Baumann, Stefano Marcellini, Terry Richard Wyatt, Claudio Grandi, J. S. White, O. C. Cooke, Ekg Sarkisyan, P. Pfeifenschneider, Peter Sherwood, R. Kowalewski, P. I. Kayal, Alexander Wagner, A. Macchiolo, S. Arcelli, E. A. Mckigney, Yoram Rozen, Beatrix Dienes, A. Biguzzi, A. J. Martin, O. Schaile, D. Lanske, R. D. Heuer, J. Ludwig, K. Runge, L. Brigliadori, J. Patt, André Schöning, Gideon Alexander, W. M. Sang, J. G. Layter, P. Bock, S. Robertson, Norbert Wermes, H. Mes, P. Scharff-Hansen, Paolo Capiluppi, I. P. Duerdoth, S. Braibant, J. Lauber, Sherry Towers, O. Sahr, Junichi Kanzaki, J. Polok, Erez Etzion, J. Couchman, A. Macpherson, T. Kawamoto, W. Mader, D. I. Futyan, C. K. Hargrove, D. Karlen, Gideon Bella, S. D. Talbot, S. W. O'Neale, R. L. Coxe, P. Hüntemeyer, Shlomit Tarem, Matthias Schröder, K. J. Anderson, M. Thiergen, A. M. Smith, P. E.L. Clarke, T. Kuhl, Stefan Schmitt, S. Orito, D. Chrisman, G. D. Long, H. J. Burckhart, Jacqueline Batley, Richard Nisius, Achim Stahl, A. D. Schaile, T. Behnke, B. Surrow, Gabriella Pasztor, Klaus Desch, C. H. Shepherd-Themistocleous, B. List, P. Vannerem, C. Sbarra, F. R. Jacob, J. P. Martin, A. M. Rossi, P. G. Estabrooks, R. K. Keeler, Richard Teuscher, R. Howard, F. Fiedler, Marco Cuffiani, R. Hawkings, K. Stoll, Stephen Lloyd, H. Landsman, Andris Skuja, C. Y. Chang, S. Petzold, S. Betts, Ehud Duchovni, S. De Jong, G. A. Snow, C. P. Ward, N. K. Watson, Arnulf Quadt, M. Hapke, S. Rosati, Tetsuro Mashimo, Shoji Asai, P. Taras, J. Goldberg, K. Stephens, M. F. Turner-Watson, K. Graham, Tara Shears, M. Jimack, Paul Kyberd, Naoko Kanaya, F. K. Loebinger, S. Söldner-Rembold, H. Rick, A. Michelini, Ivor Fleck, M. Watkins, C. R. Jones, P. Gagnon, A. Harel, A Höcker, C. Littlewood, Ikuo Ueda, D. M. Strom, J. Lu, J. Letts, Joleen Pater, T. Kobayashi, A. Klier, F. G. Oakham, W. Gorn, Zoltan Laszlo Trocsanyi, Dong Hee Kim, M. J. Oreglia, Daniel Lellouch, E. L. Barberio, A. W. Lloyd, G. W. Wilson, Takehiko Mori, I. Cohen, H. A. Neal, Peter R Hobson, Thomas E Marchant, Paolo Giacomelli, K. Sachs, Shlomo Dado, G. G. Hanson, M. Hansroul, A. A. Faust, A. Okpara, P. Mättig, Christoph Rembser, James Pinfold, R. Perez-Ochoa, R. Seuster, S. A. Robins, S.J. Dallison, M. Hauschild, Michael Hildreth, Alain Bellerive, R. J. Hemingway, G. Giacomelli, I. Lawson, J. Lillich, Christopher Hawkes, I. Trigger, M. Verzocchi, R. Liebisch, K. Ackerstaff, M. Kolrep, A. De Roeck, M. Kobel, B. W. Kennedy, D. Zer-Zion, D. R. Ward, J. R. Carter, G. N. Patrick, Sachio Komamiya, M. Harin-Dirac, V. Zacek, A. T. Watson, P. Jovanovic, Austin Ball, N. L. Rodning, Peter Krieger, Giora Mikenberg, J. W. Gary, R. J. Homer, M. S. Dixit, Frans Meijers, Satoshi Mihara, S. F. Ashby, Marcello Mannelli, S. B. Anderson, Alessandro Montanari, I. Meyer, P. Dervan, B. Poli, H. Voss, R. J. Barlow, T. P. Kokott, D. Waller, Stan Bentvelsen, S. Spagnolo, T. Saeki, Randall Sobie, G. D. Lafferty, Alessandra Fanfani, R. Davis, Guenter Duckeck, J. Grunhaus, Juergen Thomas, Claudia Ciocca, M. Fanti, D. E. Plane, G. M. Dallavalle, P. Ferrari, K. Roscoe, German Martinez, Robert McPherson, E. Torrence, J. M. Roney, W. J. McDonald, E. Clay, B. C. Shen, M. Donkers, M. Przybycień, T. Kress, Kiyotomo Kawagoe, T. Trefzger, Siegfried Bethke, D. Liu, A. K. Honma, A. A. Carter, Koichi Nagai, K. R. Hossain, Fabrizio Fabbri, A. Frey, J. Schieck, W. R. Gibson, W. G. Scott, D. C. Imrie, K. Harder, I. Nakamura, W. Mohr, Giovanni Abbiendi, G. P. Siroli, Daniele Bonacorsi, Christoph Schwick, D. R. Rust, R. M. Brown, Lorne Levinson, P. Mendez-Lorenzo, D. Glenzinski, J. von Krogh, Dezso Horvath, M. J. Losty, M. A. Thomson, M. Gruwé, D. Wetterling, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, J. A. Wilson, J. Böhme, E. K. U. Gross, R. Van Kooten, M. Sproston, F. Wäckerle, D. M. Gingrich, Georges Azuelos, E. Tsur, K. W. Bell, J. C. Hill, M. Boutemeur, F. S. Merritt, J. Bechtluft, J. A. McKenna, H. O. Ogren, Christoph Geich-Gimbel, Vakhtang Kartvelishvili, J. E. Conboy, A. Fürtjes, Lutz Feld, Gregor Herten, J. E. Pilcher, G. Gaycken, and P. G. Bright-Thomas
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Luminosity (scattering theory), Photon, 010308 nuclear & particles physics, Branching fraction, Electron–positron annihilation, Resonance, Context (language use), 01 natural sciences, 7. Clean energy, Nuclear physics, Excited state, 0103 physical sciences, High Energy Physics::Experiment, Invariant mass, 010306 general physics
Abstract: The process e+e−→γγ(γ) is studied using data recorded with the OPAL detector at LEP. The data sample taken at a centre-of-mass energy of 189 GeV corresponds to a total integrated luminosity of 178 pb−1. The measured cross-section agrees well with the expectation from QED. A fit to the angular distribution is used to obtain improved limits at 95% CL on the QED cut-off parameters: Λ+> 304 GeV and Λ−> 295 GeV as well as a mass limit for an excited electron, Me* > 306 GeV assuming equal e*ey and eeγ couplings. Graviton exchange in the context of theories with higher dimensions is excluded for scales G+< 660 GeV and G−< 634 GeV. No evidence for resonance production is found in the invariant mass spectrum of photon pairs. Limits are obtained for the cross-section times branching ratio for a resonance decaying into two photons and produced in association with another photon.
Published: 1999
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40. Measurement of the W Mass and Width in $e^{+}e^{-}$ Collisions at 183 GeV

Author: G. Abbiendi, K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, P. Bock, J. Böhme, D. Bonacorsi, M. Boutemeur, S. Braibant, P. Bright-Thomas, L. Brigliadori, R.M. Brown, H.J. Burckhart, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, C. Ciocca, P.E.L. Clarke, E. Clay, I. Cohen, J.E. Conboy, O.C. Cooke, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, G.M. Dallavalle, R. Davis, S. De Jong, A. de Roeck, P. Dervan, K. Desch, B. Dienes, M.S. Dixit, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, P.G. Estabrooks, E. Etzion, F. Fabbri, M. Fanti, A.A. Faust, F. Fiedler, M. Fierro, I. Fleck, R. Folman, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, W. Gorn, C. Grandi, K. Graham, E. Gross, J. Grunhaus, M. Gruwé, G.G. Hanson, M. Hansroul, M. Hapke, K. Harder, A. Harel, C.K. Hargrove, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, P.R. Hobson, M. Hoch, A. Hocker, K. Hoffman, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, D.C. Imrie, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, M. Jimack, C.R. Jones, P. Jovanovic, T.R. Junk, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, D.H. Kim, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, T. Kuhl, P. Kyberd, G.D. Lafferty, H. Landsman, D. Lanske, J. Lauber, S.R. Lautenschlager, I. Lawson, J.G. Layter, D. Lazic, A.M. Lee, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, D. Liu, A. Macchiolo, A. Macpherson, W. Mader, M. Mannelli, S. Marcellini, C. Markopoulos, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, J. Polok, M. Przybycień, C. Rembser, H. Rick, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, B. Schmitt, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Sittler, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, S. Spagnolo, M. Sproston, A. Stahl, K. Stephens, J. Steuerer, K. Stoll, D. Strom, R. Ströhmer, B. Surrow, S.D. Talbot, S. Tanaka, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, J. Thomas, M.A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, I. Ueda, R. Van Kooten, P. Vannerem, M. Verzocchi, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, FOS: Physical sciences, 01 natural sciences, Direct measure, Standard Model, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Nuclear Experiment, Particle Physics - Experiment
Abstract: Using a data sample of 57 pb-1 recorded at a centre-of-mass energy of 183 GeV with the Opal detector at LEP, 282 W+W- -> qqqq and 300 W+W- -> qqlnu candidate events are used to obtain a measurement of the mass of the W boson, W_W = 80.39 +- 0.13(stat.) +- 0.05(syst.) GeV assuming the Standard Model relation between M_W and Gam_W. A second fit provides a direct measure of the width of the W boson and gives Gam_W = 1.96 +- 0.34(stat.) +- 0.20(syst.) GeV. These results are combined with previous OPAL results to obtain M_W = 80.38 +- 0.12(stat.) +- 0.05(syst.) GeV and Gam_W = 1.84 +- 0.32(stat.) +- 0.20(syst.) GeV., 21 pages, LaTeX, 4 eps figs included, submitted to Physics Letters B
Published: 1998

41. A Measurement of Rb using a Double Tagging Method

Author: Abbiendi, G, Ackerstaff, K, Alexander, G, Allison, J, Altekamp, N, Anderson, KJ, Anderson, S, Arcelli, S, Asai, S, Ashby, SF, Axen, D, Cooke, OC, Herten, G, Lellouch, D, Schmitt, S, Letts, J, Rodning, N, Strohmer, R, Charlton, DG, Mannelli, M, Barberio, E, Sproston, M, Przybycien, M, Fanti, M, Nisius, R, Hansroul, M, Levinson, L, Baumann, S, Shears, TG, Roney, JM, Liebisch, R, Mes, H, Biebel, O, Seuster, R, Dubbert, J, Jeremie, H, List, B, Soldner-Rembold, S, Littlewood, C, Towers, S, De Jong, S, Mihara, S, Bethke, S, Futyan, DI, Perez-Ochoa, R, Howard, R, Lloyd, AW, Brown, RM, Stoll, K, Lloyd, SL, O'Neale, SW, Faust, AA, Klier, A, Loebinger, FK, Marcellini, S, Long, GD, Verzocchi, M, Estabrooks, PG, Ogren, HO, Rembser, C, Losty, MJ, Couyoumtzelis, C, von Torne, E, Ludwig, J, Petzold, S, Gagnon, P, Krieger, P, Shen, BC, Liu, D, Pilcher, JE, Roscoe, K, Bechtluft, J, Hill, JC, Bloodworth, IJ, Grunhaus, J, Rick, H, Lautenschlager, SR, Azuelos, G, Macchiolo, A, Burckhart, HJ, McPherson, RA, Chrisman, D, Honma, AK, Rossi, AM, Bonacorsi, D, Bell, KW, Coxe, RL, Neal, HA, Kartvelishvili, V, Clarke, PEL, Mashimo, T, Mattig, P, Kokott, TP, Desch, K, Montanari, A, Mori, T, Batley, JR, Palinkas, J, Siroli, GP, Bentvelsen, S, Kawamoto, T, McMahon, TJ, Rozen, Y, Bright-Thomas, P, Runge, K, Watkins, PM, Davis, R, Jones, CR, Schmitt, B, Gruwe, M, Voss, H, Lanske, D, Talbot, SD, Markopoulos, C, Runolfsson, O, Harder, K, Carnegie, RK, Watson, AT, Rust, DR, Skuja, A, Capiluppi, P, Komamiya, S, Nakamura, I, Sachs, K, Conboy, JE, Saeki, T, Eatough, D, Kobayashi, T, Sobie, R, Hemingway, RJ, Trocsanyi, Z, Miller, DJ, Sahr, O, Huntemeyer, P, Dado, S, Sang, WM, Tanaka, S, Lauber, J, Pater, JR, Betts, S, Sarkisyan, EKG, Fierro, M, Kuhl, T, Teuscher, R, Wackerle, F, Sbarra, C, Kayal, PI, Duckeck, G, Schaile, AD, Tsur, E, Poffenberger, P, Carter, AA, Schaile, O, Turner-Watson, MF, Watson, NK, Hargrove, CK, Menke, S, Hillier, SJ, Mader, W, Wagner, A, Gross, E, Scharf, F, Igo-Kemenes, P, Sherwood, P, Jovanovic, P, Michelini, A, Bobinski, M, Homer, RJ, Hauschild, M, Keeler, RK, Odorici, F, Karlen, D, Schwick, C, Scott, WG, Pfeifenschneider, P, Bartoldus, R, Steuerer, J, Bird, SD, Hapke, M, Thomson, MA, Hawkings, R, Oreglia, MJ, Shepherd-Themistocleous, CH, Wells, PS, Hossain, KR, Wermes, N, Gary, JW, Kluth, S, Nellen, B, Braibant, S, Fleck, I, Robertson, S, del Pozo, LA, Schoning, A, White, JS, Martin, JP, Jacob, FR, Gascon, J, Wilson, GW, Ciocca, C, Pinfold, J, Strom, D, Wilson, JA, Barlow, RJ, Wyatt, TR, von Krogh, J, Patt, J, Cohen, I, McKenna, J, Etzion, E, Yamashita, S, Mir, R, Kennedy, BW, Yekutieli, G, de Roeck, A, Robins, SA, Torrence, E, Herndon, M, Zacek, V, Lawson, I, Dixit, MS, Folman, R, Zer-Zion, D, Orito, S, Kress, T, Bock, P, Evans, HG, Vannerem, P, Jawahery, A, OPAL Collaboration, Gascon-Shotkin, SM, Martinez, G, Biguzzi, A, Merritt, FS, Schieck, J, Furtjes, A, Macpherson, A, Bohme, J, Mohr, W, Chang, CY, Snow, GA, Hobson, PR, Meyer, J, Behnke, T, Bellerive, A, Tarem, S, Oakham, FG, Burgard, C, Burgin, R, Turcot, AS, Cuffiani, M, Hildreth, MD, Martin, AJ, Duchovni, E, McDonald, WJ, Thiergen, M, Carter, JR, Gaycken, G, Mikenberg, G, Geich-Gimbel, C, Patrick, GN, Surrow, B, Horvath, D, Layter, JG, Ward, CP, Kobel, M, Brigliadori, L, Giacomelli, G, Schroder, M, Nagai, K, Giacomelli, P, Junk, TR, Van Kooten, R, Dallavalle, GM, Gibson, V, Hanson, GG, Gibson, WR, Polok, J, Trigger, I, Kawagoe, K, Kyberd, P, Gingrich, DM, Stahl, A, Pasztor, G, Glenzinski, D, Koetke, DS, Ward, DR, Duerdoth, IP, Mckigney, EA, Goldberg, J, Kolrep, M, Lazic, D, Gorn, W, Blobel, V, Plane, DE, Ball, AH, Lafferty, GD, Fiedler, F, Bella, G, Grandi, C, Schumacher, M, Heuer, RD, Sittler, A, Boutemeur, M, Lee, AM, Scharff-Hansen, P, Hocker, A, Stephens, K, Jimack, M, Clay, E, Smith, AM, Hartmann, C, Hawkes, CM, Dienes, B, Taras, P, Imrie, DC, Ishii, K, Fabbri, F, Kellogg, RG, Meijers, F, and Kowalewski, RV
Subjects: Microvertex detector, Particle physics, Physics and Astronomy (miscellaneous), Gluons, Hadron, FOS: Physical sciences, Value (computer science), Electron, 01 natural sciences, High momentum, Standard Model, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), Quark fragmentation, Heavy quarks, 0103 physical sciences, 010306 general physics, Mass tag, Engineering (miscellaneous), Physics, Muon, 010308 nuclear & particles physics, Hadronic Z(0) decays, Meson production, TAU-lifetime, Multiplicity, Simulated data, High Energy Physics::Experiment
Abstract: The fraction of Z to bbbar events in hadronic Z decays has been measured by the OPAL experiment using the data collected at LEP between 1992 and 1995. The Z to bbbar decays were tagged using displaced secondary vertices, and high momentum electrons and muons. Systematic uncertainties were reduced by measuring the b-tagging efficiency using a double tagging technique. Efficiency correlations between opposite hemispheres of an event are small, and are well understood through comparisons between real and simulated data samples. A value of Rb = 0.2178 +- 0.0011 +- 0.0013 was obtained, where the first error is statistical and the second systematic. The uncertainty on Rc, the fraction of Z to ccbar events in hadronic Z decays, is not included in the errors. The dependence on Rc is Delta(Rb)/Rb = -0.056*Delta(Rc)/Rc where Delta(Rc) is the deviation of Rc from the value 0.172 predicted by the Standard Model. The result for Rb agrees with the value of 0.2155 +- 0.0003 predicted by the Standard Model., 42 pages, LaTeX, 14 eps figures included, submitted to European Physical Journal C
Published: 1998

42. Search for Higgs Bosons and New Particles Decaying into Two Photons at sqrt(s) = 183 GeV

Author: K Ackerstaff, G Alexander, J Allison, N Altekamp, K.J Anderson, S Anderson, S Arcelli, S Asai, S.F Ashby, D Axen, G Azuelos, A.H Ball, E Barberio, R.J Barlow, R Bartoldus, J.R Batley, S Baumann, J Bechtluft, T Behnke, K.W Bell, G Bella, S Bentvelsen, S Bethke, S Betts, O Biebel, A Biguzzi, S.D Bird, V Blobel, I.J Bloodworth, M Bobinski, P Bock, J Böhme, M Boutemeur, S Braibant, P Bright-Thomas, R.M Brown, H.J Burckhart, C Burgard, R Bürgin, P Capiluppi, R.K Carnegie, A.A Carter, J.R Carter, C.Y Chang, D.G Charlton, D Chrisman, C Ciocca, P.E.L Clarke, E Clay, I Cohen, J.E Conboy, O.C Cooke, C Couyoumtzelis, R.L Coxe, M Cuffiani, S Dado, G.M Dallavalle, R Davis, S De Jong, L.A del Pozo, A de Roeck, K Desch, B Dienes, M.S Dixit, M Doucet, J Dubbert, E Duchovni, G Duckeck, I.P Duerdoth, D Eatough, P.G Estabrooks, E Etzion, H.G Evans, F Fabbri, A Fanfani, M Fanti, A.A Faust, F Fiedler, M Fierro, H.M Fischer, I Fleck, R Folman, A Fürtjes, D.I Futyan, P Gagnon, J.W Gary, J Gascon, S.M Gascon-Shotkin, C Geich-Gimbel, T Geralis, G Giacomelli, P Giacomelli, V Gibson, W.R Gibson, D.M Gingrich, D Glenzinski, J Goldberg, W Gorn, C Grandi, E Gross, J Grunhaus, M Gruwé, G.G Hanson, M Hansroul, M Hapke, C.K Hargrove, C Hartmann, M Hauschild, C.M Hawkes, R Hawkings, R.J Hemingway, M Herndon, G Herten, R.D Heuer, M.D Hildreth, J.C Hill, S.J Hillier, P.R Hobson, A Hocker, R.J Homer, A.K Honma, D Horváth, K.R Hossain, R Howard, P Hüntemeyer, P Igo-Kemenes, D.C Imrie, K Ishii, F.R Jacob, A Jawahery, H Jeremie, M Jimack, A Joly, C.R Jones, P Jovanovic, T.R Junk, D Karlen, V Kartvelishvili, K Kawagoe, T Kawamoto, P.I Kayal, R.K Keeler, R.G Kellogg, B.W Kennedy, A Klier, S Kluth, T Kobayashi, M Kobel, D.S Koetke, T.P Kokott, M Kolrep, S Komamiya, R.V Kowalewski, T Kress, P Krieger, J von Krogh, P Kyberd, G.D Lafferty, D Lanske, J Lauber, S.R Lautenschlager, I Lawson, J.G Layter, D Lazic, A.M Lee, E Lefebvre, D Lellouch, J Letts, L Levinson, R Liebisch, B List, C Littlewood, A.W Lloyd, S.L Lloyd, F.K Loebinger, G.D Long, M.J Losty, J Ludwig, D Liu, A Macchiolo, A Macpherson, M Mannelli, S Marcellini, C Markopoulos, A.J Martin, J.P Martin, G Martinez, T Mashimo, P Mättig, W.J McDonald, J McKenna, E.A Mckigney, T.J McMahon, R.A McPherson, F Meijers, S Menke, F.S Merritt, H Mes, J Meyer, A Michelini, S Mihara, G Mikenberg, D.J Miller, R Mir, W Mohr, A Montanari, T Mori, K Nagai, I Nakamura, H.A Neal, B Nellen, R Nisius, S.W O'Neale, F.G Oakham, F Odorici, H.O Ogren, M.J Oreglia, S Orito, J Pálinkás, G Pásztor, J.R Pater, G.N Patrick, J Patt, R Perez-Ochoa, S Petzold, P Pfeifenschneider, J.E Pilcher, J Pinfold, D.E Plane, P Poffenberger, B Poli, J Polok, M Przybycień, C Rembser, H Rick, S Robertson, S.A Robins, N Rodning, J.M Roney, K Roscoe, A.M Rossi, Y Rozen, K Runge, O Runolfsson, D.R Rust, K Sachs, T Saeki, O Sahr, W.M Sang, E.K.G Sarkisyan, C Sbarra, A.D Schaile, O Schaile, F Scharf, P Scharff-Hansen, J Schieck, B Schmitt, S Schmitt, A Schöning, T Schorner, M Schröder, M Schumacher, C Schwick, W.G Scott, R Seuster, T.G Shears, B.C Shen, C.H Shepherd-Themistocleous, P Sherwood, G.P Siroli, A Sittler, A Skuja, A.M Smith, G.A Snow, R Sobie, S Söldner-Rembold, M Sproston, A Stahl, K Stephens, J Steuerer, K Stoll, D Strom, R Ströhmer, R Tafirout, S.D Talbot, S Tanaka, P Taras, S Tarem, R Teuscher, M Thiergen, M.A Thomson, E von Törne, E Torrence, S Towers, I Trigger, Z Trócsányi, E Tsur, A.S Turcot, M.F Turner-Watson, R Van Kooten, P Vannerem, M Verzocchi, P Vikas, H Voss, F Wäckerle, A Wagner, C.P Ward, D.R Ward, P.M Watkins, A.T Watson, N.K Watson, P.S Wells, N Wermes, J.S White, G.W Wilson, J.A Wilson, T.R Wyatt, S Yamashita, G Yekutieli, V Zacek, and D Zer-Zion
Subjects: Physics, Nuclear and High Energy Physics, Gauge boson, Particle physics, Photon, 010308 nuclear & particles physics, Hadron, Scalar (mathematics), High Energy Physics::Phenomenology, FOS: Physical sciences, Fermion, 01 natural sciences, 3. Good health, Standard Model, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, Higgs boson, High Energy Physics::Experiment, 010306 general physics, Particle Physics - Experiment, Boson
Abstract: A search for the resonant production of high mass photon pairs associated with a leptonic or hadronic system has been performed using a data sample of 57.7 pb-1 collected at an average center-of-mass energy of 182.6 GeV with the OPAL detector at LEP. No evidence for contributions from non-Standard Model physics processes was observed. The observed candidates are used to place limits on BR (H to gamma gamma) assuming a Standard Model production rate for Higgs boson masses up to 92 GeV, and on the production cross section for a scalar resonance decaying into di-photons up to a mass of 170 GeV. Upper limits on the product of cross section and branching ratios, sigma(e+e- to XY) * BR(X to gamma gamma) * BR(Y to f fbar) as low as 70fb are obtained over the M(X) range 10 - 170 GeV for the case where 10 < M(Y) < 160 GeV and M(X)+M(Y) > 90 GeV, independent of the nature of Y provided it decays to a fermion pair and has negligible width. Higgs scalars which couple only to gauge bosons at Standard Model strength are ruled out up to a mass of 90.0 GeV at the 95% confidence level. Limits are also placed on non-minimal Higgs sectors having triplet representations., 21 pages, LaTeX, 4 eps figures included, submitted to Physics Letters B
Published: 1998

43. Measurement of the average polarization of b baryons in hadronic $Z^0$ decays

Author: G. Abbiendi, K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, M. Bobinski, P. Bock, J. Böhme, D. Bonacorsi, M. Boutemeur, S. Braibant, P. Bright-Thomas, L. Brigliadori, R.M. Brown, H.J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, C. Ciocca, P.E.L. Clarke, E. Clay, I. Cohen, J.E. Conboy, O.C. Cooke, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, G.M. Dallavalle, R. Davis, S. De Jong, L.A. del Pozo, A. de Roeck, K. Desch, B. Dienes, M.S. Dixit, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, P.G. Estabrooks, E. Etzion, H.G. Evans, F. Fabbri, M. Fanti, A.A. Faust, F. Fiedler, M. Fierro, I. Fleck, R. Folman, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, W. Gorn, C. Grandi, E. Gross, J. Grunhaus, M. Gruwé, G.G. Hanson, M. Hansroul, M. Hapke, K. Harder, C.K. Hargrove, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, S.J. Hillier, P.R. Hobson, A. Hocker, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, D.C. Imrie, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, M. Jimack, C.R. Jones, P. Jovanovic, T.R. Junk, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, T. Kuhl, P. Kyberd, G.D. Lafferty, D. Lanske, J. Lauber, S.R. Lautenschlager, I. Lawson, J.G. Layter, D. Lazic, A.M. Lee, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, D. Liu, A. Macchiolo, A. Macpherson, W. Mader, M. Mannelli, S. Marcellini, C. Markopoulos, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, J. Polok, M. Przybycień, C. Rembser, H. Rick, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, B. Schmitt, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Sittler, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, M. Sproston, A. Stahl, K. Stephens, J. Steuerer, K. Stoll, D. Strom, R. Ströhmer, B. Surrow, S.D. Talbot, S. Tanaka, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, M.A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, R. Van Kooten, P. Vannerem, M. Verzocchi, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion
Subjects: Physics, Semileptonic decay, Nuclear and High Energy Physics, Particle physics, Missing energy, 010308 nuclear & particles physics, Hadron, Nuclear Theory, High Energy Physics::Phenomenology, FOS: Physical sciences, Lambda baryon, 01 natural sciences, High Energy Physics - Experiment, Baryon, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, High Energy Physics::Experiment, Baryon number, Neutrino, 010306 general physics, Particle Physics - Experiment, Lepton
Abstract: In the Standard Model, b quarks produced in e^+e^- annihilation at the Z^0 peak have a large average longitudinal polarization of -0.94. Some fraction of this polarization is expected to be transferred to b-flavored baryons during hadronization. The average longitudinal polarization of weakly decaying b baryons, , is measured in approximately 4.3 million hadronic Z^0 decays collected with the OPAL detector between 1990 and 1995 at LEP. Those b baryons that decay semileptonically and produce a \Lambda baryon are identified through the correlation of the baryon number of the \Lambda and the electric charge of the lepton. In this semileptonic decay, the ratio of the neutrino energy to the lepton energy is a sensitive polarization observable. The neutrino energy is estimated using missing energy measurements. From a fit to the distribution of this ratio, the value = -0.56^{+0.20}_{-0.13} +/- 0.09 is obtained, where the first error is statistical and the second systematic., Comment: 19 pages, LaTeX, 4 eps figures included, submitted to Phys. Lett. B
Published: 1998

44. Di-Jet Production in Photon-Photon Collisions at $\sqrt{s}_{ee}$ = 161 and 172 GeV

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barillari, T., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bobinski, M., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., del Pozo, L.A., De Roeck, A., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Evans, H.G., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hillier, S.J., Hobson, P.R., Hocker, James Andrew, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Physics, Particle physics, Photon, Physics and Astronomy (miscellaneous), 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Monte Carlo method, Perturbative QCD, Parton, Jet (particle physics), 01 natural sciences, 0103 physical sciences, Rapidity, High Energy Physics::Experiment, Center of mass, 010306 general physics, Engineering (miscellaneous), Event (particle physics), Particle Physics - Experiment
Abstract: Di-jet production is studied in collisions of quasi-real photons radiated by the LEP beams at e+e- centre-of-mass energies 161 and 172 GeV. The jets are reconstructed using a cone jet finding algorithm. The angular distributions of direct and double-resolved processes are measured and compared to the predictions of leading order and next-to-leading order perturbative QCD. The jet energy profiles are also studied. The inclusive two-jet cross-section is measured as a function of transverse energy and rapidity and compared to next-to-leading order perturbative QCD calculations. The inclusive two-jet cross-section as a function of rapidity is compared to the prediction of the leading order Monte Carlo generators PYTHIA and PHOJET. The Monte Carlo predictions are calculated with different parametrisations of the parton distributions of the photon. The influence of the `underlying event' has been studied to reduce the model dependence of the predicted jet cross-sections from the Monte Carlo generators. Di-jet production is studied in collisions of quasi-real photons radiated by the LEP beams at e+e- centre-of-mass energies 161 and 172 GeV. The jets are reconstructed using a cone jet finding algorithm. The angular distributions of direct and double-resolved processes are measured and compared to the predictions of leading order and next-to-leading order perturbative QCD. The jet energy profiles are also studied. The inclusive two-jet cross-section is measured as a function of transverse energy and rapidity and compared to next-to-leading order perturbative QCD calculations. The inclusive two-jet cross-section as a function of rapidity is compared to the prediction of the leading order Monte Carlo generators PYTHIA and PHOJET. The Monte Carlo predictions are calculated with different parametrisations of the parton distributions of the photon. The influence of the `underlying event' has been studied to reduce the model dependence of the predicted jet cross-sections from the Monte Carlo generators. Di-jet production is studied in collisions of quasi-real photons radiated by the LEP beams at e+e- centre-of-mass energies 161 and 172 GeV. The jets are reconstructed using a cone jet finding algorithm. The angular distributions of direct and double-resolved processes are measured and compared to the predictions of leading order and next-to-leading order perturbative QCD. The jet energy profiles are also studied. The inclusive two-jet cross-section is measured as a function of transverse energy and rapidity and compared to next-to-leading order perturbative QCD calculations. The inclusive two-jet cross-section as a function of rapidity is compared to the prediction of the leading order Monte Carlo generators PYTHIA and PHOJET. The Monte Carlo predictions are calculated with different parametrisations of the parton distributions of the photon. The influence of the `underlying event' has been studied to reduce the model dependence of the predicted jet cross-sections from the Monte Carlo generators.
Published: 1998

45. Measurement of the Michel Parameters in Leptonic Tau Decays

Author: Ackerstaff, K., Alexander, G., Allison, J., Altekamp, N., Anderson, K. J., Anderson, S., Arcelli, S., Asai, S., Ashby, S. F., Axen, D., Azuelos, G., Ball, A. H., Barberio, E., Barlow, R. J., Bartoldus, R., Batley, J. R., Baumann, S., Bechtluft, J., Behnke, T., Bell, K. W., Bella, G., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S. D., Blobel, V., Bloodworth, I. J., Bobinski, M., Bock, P., Bohme, J., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brown, R. M., Burckhart, H. J., Burgard, C., Burgin, R., Capiluppi, P., Carnegie, R. K., Carter, A. A., Carter, J. R., Chang, C. Y., Charlton, D. G., Chrisman, D., Ciocca, C., Clarke, P. E. L., Clay, E., Cohen, I., Conboy, J. E., Cooke, O. C., Couyoumtzelis, C., Coxe, R. L., Cuffiani, M., Dado, S., Dallavalle, G. M., Davis, R., Jong, S., Del Pozo, L. A., Roeck, A., Desch, K., Dienes, B., Dixit, M. S., Doucet, M., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I. P., Eatough, D., Estabrooks, P. G., Etzion, E., Evans, H. G., Fabbri, F., Fanfani, A., Fanti, M., Faust, A. A., Fiedler, F., Fierro, M., Fischer, H. M., Fleck, I., Folman, R., Furtjes, A., Futyan, D. I., Gagnon, P., Gary, J. W., Gascon, J., Gascon-Shotkin, S. M., Geich-Gimbel, C., Geralis, T., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W. R., Gingrich, D. M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G. G., Hansroul, M., Hapke, M., Hargrove, C. K., Hartmann, C., Hauschild, M., Hawkes, C. M., Hawkings, R., Hemingway, R. J., Herndon, M., Herten, G., Heuer, R. D., Hildreth, M. D., Hill, J. C., Hillier, S. J., Hobson, P. R., Hocker, A., Homer, R. J., Honma, A. K., Horvath, D., Hossain, K. R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D. C., Ishii, K., Jacob, F. R., Jawahery, A., Jeremie, H., Jimack, M., Joly, A., Jones, C. R., Jovanovic, P., Junk, T. R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P. I., Keeler, R. K., Kellogg, R. G., Kennedy, B. W., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D. S., Kokott, T. P., Kolrep, M., Komamiya, S., Kowalewski, R. V., Kress, T., Krieger, P., Krogh, J., Kyberd, P., Lafferty, G. D., Lanske, D., Lauber, J., Lautenschlager, S. R., Lawson, I., Layter, J. G., Lazic, D., Lee, A. M., Lefebvre, E., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A. W., Lloyd, S. L., Loebinger, F. K., Long, G. D., Losty, M. J., Ludwig, J., Liu, D., Macchiolo, A., Macpherson, A., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A. J., Martin, J. P., Martinez, G., Mashimo, T., Mattig, P., Mcdonald, W. J., Mckenna, J., Mckigney, E. A., Mcmahon, T. J., Mcpherson, R. A., Meijers, F., Menke, S., Merritt, F. S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D. J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H. A., Nellen, B., Nisius, R., O Neale, S. W., Oakham, F. G., Odorici, F., Ogren, H. O., Oreglia, M. J., Orito, S., Pálinkás, J., Pásztor, G., Pater, J. R., Patrick, G. N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J. E., Pinfold, J., Plane, D. E., Poffenberger, P., Poli, B., Polok, J., Przybycieá, M., Rembser, C., Rick, H., Robertson, S., Robins, S. A., Rodning, N., Roney, J. M., Roscoe, K., Rossi, A. M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D. R., Sachs, K., Saeki, T., Sahr, O., Sang, W. M., Sarkisyan, E. K. G., Sbarra, C., Schaile, A. D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Bernd Schmitt, Schmitt, S., Schöning, A., Schorner, T., Schroder, M., Schumacher, M., Schwick, C., Scott, W. G., Seuster, R., Shears, T. G., Shen, B. C., Shepherd-Themistocleous, C. H., Sherwood, P., Siroli, G. P., Sittler, A., Skuja, A., Smith, A. M., Snow, G. A., Sobie, R., Soldner-Rembold, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, D., Ströhmer, R., Tafirout, R., Talbot, S. D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomson, M. A., Torne, E., Torrence, E., Towers, S., Trigger, I., Trócsányi, Z., Tsur, E., Turcot, A. S., Turner-Watson, M. F., Kooten, R., Vannerem, P., Verzocchi, M., Vikas, P., Voss, H., Wäckerle, F., Wagner, A., Ward, C. P., Ward, D. R., Watkins, P. M., Watson, A. T., Watson, N. K., Wells, P. S., Wermes, N., White, J. S., Wilson, G. W., Wilson, J. A., Wyatt, T. R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Physics, Coupling constant, Gauge boson, Particle physics, Luminosity (scattering theory), Physics and Astronomy (miscellaneous), Neutral current, 010308 nuclear & particles physics, Monte Carlo method, FOS: Physical sciences, 01 natural sciences, 7. Clean energy, Standard Model, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, Michel parameters, High Energy Physics::Experiment, 010306 general physics, Engineering (miscellaneous), Particle Physics - Experiment, Lepton
Abstract: The Michel parameters of the leptonic tau decays are measured using the OPAL detector at LEP. The Michel parameters are extracted from the energy spectra of the charged decay leptons and from their energy-energy correlations. A new method involving a global likelihood fit of Monte Carlo generated events with complete detector simulation and background treatment has been applied to the data recorded at center-of-mass energies close to sqrt(s) = M(Z) corresponding to an integrated luminosity of 155 pb-1 during the years 1990 to 1995. If e-mu universality is assumed and inferring the tau polarization from neutral current data, the measured Michel parameters are extracted. Limits on non-standard coupling constants and on the masses of new gauge bosons are obtained. The results are in agreement with the V-A prediction of the Standard Model., 32 pages, LaTeX, 9 eps figures included, submitted to the European Physical Journal C
Published: 1998

46. Measurement of the Q(2) evolution of the photon structure function F-2(gamma)

Author: K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, T. Barillari, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, C. Beeston, T. Behnke, A.N. Bell, K.W. Bell, G. Bella, S. Bentvelsen, S. Bethke, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, J.E. Bloomer, M. Bobinski, P. Bock, D. Bonacorsi, M. Boutemeur, B.T. Bouwens, S. Braibant, L. Brigliadori, R.M. Brown, H.J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, P.E.L. Clarke, I. Cohen, J.E. Conboy, O.C. Cooke, M. Cuffiani, S. Dado, C. Dallapiccola, G.M. Dallavalle, R. Davies, S. De Jong, L.A. del Pozo, K. Desch, B. Dienes, M.S. Dixit, E. do Couto e Silva, M. Doucet, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, J.E.G. Edwards, P.G. Estabrooks, H.G. Evans, M. Evans, F. Fabbri, M. Fanti, A.A. Faust, F. Fiedler, M. Fierro, H.M. Fischer, I. Fleck, R. Folman, D.G. Fong, M. Foucher, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, N.I. Geddes, C. Geich-Gimbel, T. Geralis, G. Giacomelli, P. Giacomelli, R. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, M.J. Goodrick, W. Gorn, C. Grandi, E. Gross, J. Grunhaus, M. Gruwé, C. Hajdu, G.G. Hanson, M. Hansroul, M. Hapke, C.K. Hargrove, P.A. Hart, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, S.J. Hillier, P.R. Hobson, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, D.E. Hutchcroft, P. Igo-Kemenes, D.C. Imrie, M.R. Ingram, K. Ishii, A. Jawahery, P.W. Jeffreys, H. Jeremie, M. Jimack, A. Joly, C.R. Jones, G. Jones, M. Jones, U. Jost, P. Jovanovic, T.R. Junk, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, J. Kirk, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, T. Kress, P. Krieger, J. von Krogh, P. Kyberd, G.D. Lafferty, R. Lahmann, W.P. Lai, D. Lanske, J. Lauber, S.R. Lautenschlager, J.G. Layter, D. Lazic, A.M. Lee, E. Lefebvre, D. Lellouch, J. Letts, L. Levinson, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, A. Macchiolo, A. Macpherson, M. Mannelli, S. Marcellini, C. Markus, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, G. Mikenberg, D.J. Miller, A. Mincer, R. Mir, W. Mohr, A. Montanari, T. Mori, M. Morii, U. Müller, S. Mihara, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, A. Oh, N.J. Oldershaw, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, M.J. Pearce, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, B. Poli, A. Posthaus, D.L. Rees, D. Rigby, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, A. Rooke, E. Ros, A.M. Rossi, P. Routenburg, Y. Rozen, K. Runge, O. Runolfsson, U. Ruppel, D.R. Rust, R. Rylko, K. Sachs, T. Saeki, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, P. Schenk, J. Schieck, P. Schleper, B. Schmitt, S. Schmitt, A. Schöning, M. Schröder, H.C. Schultz-Coulon, M. Schumacher, C. Schwick, W.G. Scott, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Sittler, A. Skillman, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, R.W. Springer, M. Sproston, K. Stephens, J. Steuerer, B. Stockhausen, K. Stoll, D. Strom, P. Szymanski, R. Tafirout, S.D. Talbot, S. Tanaka, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, M.A. Thomson, E. von Törne, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, P. Utzat, R. Van Kooten, M. Verzocchi, P. Vikas, E.H. Vokurka, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, B. Wilkens, G.W. Wilson, J.A. Wilson, G. Wolf, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Range (particle radiation), 010308 nuclear & particles physics, 2-Photon Production Processes, Microvertex Detector, FOS: Physical sciences, LEP, Generator, 01 natural sciences, Photon structure function, Luminosity, High Energy Physics - Experiment, Q2, Scattering, GEV2, High Energy Physics - Experiment (hep-ex), High-Energy, 0103 physical sciences, Leading Order, 010306 general physics, Opal Detector, Particle Physics - Experiment
Abstract: New measurements are presented of the photon structure function F_2^gamma(Q) at four values of Q^2 between 9 and 59 GeV/c^2 based on data collected with the OPAL detector at centre-of-mass energies of 161-172 GeV, with a total integrated luminosity of 18.1 pb^-1. The evolution of F_2^gamma with Q^2 in bins of x is determined in the Q^2 range from 1.86 to 135 GeV/c^2 using data taken at centre-of-mass energies of 91 GeV and 161-172 GeV. F_2^gamma is observed to increase with Q^2 with a slope of 1/alpha_em dF_2^gamma/dln(Q^2) = 0.10 +0.05 -0.03 measured in the range 0.1 < x < 0.6., 22 pages, LaTeX, 4 eps figures included, accepted by Phys. Lett. B
Published: 1998

47. Production of Chi_c2 Mesons in Photon-Photon Collisions at LEP

Author: K. Ackerstaff, G. Alexander, J. Allison, N. Altekamp, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, S.F. Ashby, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, T. Barillari, R.J. Barlow, R. Bartoldus, J.R. Batley, S. Baumann, J. Bechtluft, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, S. Betts, O. Biebel, A. Biguzzi, S.D. Bird, V. Blobel, I.J. Bloodworth, M. Bobinski, P. Bock, J. Böhme, M. Boutemeur, S. Braibant, P. Bright-Thomas, R.M. Brown, H.J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, D.G. Charlton, D. Chrisman, C. Ciocca, P.E.L. Clarke, E. Clay, I. Cohen, J.E. Conboy, O.C. Cooke, C. Couyoumtzelis, R.L. Coxe, M. Cuffiani, S. Dado, G.M. Dallavalle, R. Davis, S. De Jong, L.A. del Pozo, A. de Roeck, K. Desch, B. Dienes, M.S. Dixit, J. Dubbert, E. Duchovni, G. Duckeck, I.P. Duerdoth, D. Eatough, P.G. Estabrooks, E. Etzion, H.G. Evans, F. Fabbri, A. Fanfani, M. Fanti, A.A. Faust, F. Fiedler, M. Fierro, I. Fleck, R. Folman, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, D. Glenzinski, J. Goldberg, W. Gorn, C. Grandi, E. Gross, J. Grunhaus, M. Gruwé, G.G. Hanson, M. Hansroul, M. Hapke, K. Harder, C.K. Hargrove, C. Hartmann, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, M. Herndon, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, S.J. Hillier, P.R. Hobson, A. Hocker, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, D.C. Imrie, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, M. Jimack, C.R. Jones, P. Jovanovic, T.R. Junk, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, P.I. Kayal, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, M. Kolrep, S. Komamiya, R.V. Kowalewski, T. Kress, P. Krieger, J. von Krogh, T. Kuhl, P. Kyberd, G.D. Lafferty, D. Lanske, J. Lauber, S.R. Lautenschlager, I. Lawson, J.G. Layter, D. Lazic, A.M. Lee, D. Lellouch, J. Letts, L. Levinson, R. Liebisch, B. List, C. Littlewood, A.W. Lloyd, S.L. Lloyd, F.K. Loebinger, G.D. Long, M.J. Losty, J. Ludwig, D. Liu, A. Macchiolo, A. Macpherson, W. Mader, M. Mannelli, S. Marcellini, C. Markopoulos, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, R.A. McPherson, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, S. Mihara, G. Mikenberg, D.J. Miller, R. Mir, W. Mohr, A. Montanari, T. Mori, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, R. Perez-Ochoa, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, B. Poli, J. Polok, M. Przybycień, C. Rembser, H. Rick, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, K. Roscoe, A.M. Rossi, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, K. Sachs, T. Saeki, O. Sahr, W.M. Sang, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, J. Schieck, B. Schmitt, S. Schmitt, A. Schöning, M. Schröder, M. Schumacher, C. Schwick, W.G. Scott, R. Seuster, T.G. Shears, B.C. Shen, C.H. Shepherd-Themistocleous, P. Sherwood, G.P. Siroli, A. Sittler, A. Skuja, A.M. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, M. Sproston, A. Stahl, K. Stephens, J. Steuerer, K. Stoll, D. Strom, R. Ströhmer, B. Surrow, S.D. Talbot, S. Tanaka, P. Taras, S. Tarem, R. Teuscher, M. Thiergen, M.A. Thomson, E. von Törne, E. Torrence, S. Towers, I. Trigger, Z. Trócsányi, E. Tsur, A.S. Turcot, M.F. Turner-Watson, R. Van Kooten, P. Vannerem, M. Verzocchi, H. Voss, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P.S. Wells, N. Wermes, J.S. White, G.W. Wilson, J.A. Wilson, T.R. Wyatt, S. Yamashita, G. Yekutieli, V. Zacek, and D. Zer-Zion
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Photon, Meson, 010308 nuclear & particles physics, Branching fraction, Detector, FOS: Physical sciences, 01 natural sciences, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, Production (computer science), High Energy Physics::Experiment, Channel (broadcasting), 010306 general physics, Particle Physics - Experiment
Abstract: We present an observation at LEP of the production of chi_c2 mesons in the collisions of two quasi-real photons using the OPAL detector. The chi_c2 mesons are reconstructed in the decay channel Chi_c2 to J/psi gamma to l+l- gamma (with l= e,mu) using all data taken at e+e- centre-of-mass energies of 91 and 183 GeV, corresponding to integrated luminosities of 167 and 55 pb-1 respectively. The two-photon width of the Chi_2 is determined to be 1.76 +- 0.47 +- 0.37 +- 0.15 keV where the first error is statistical, the second is systematic and the third comes from branching ratio uncertainties., Comment: 18 pages, LaTeX, 6 eps figures included, submitted to Physics Letters B
Published: 1998
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48. Search for chargino and neutralino production at root s=170 and 172 GeV at LEP

Author: D. R. Rust, L. Brigliadori, Kiyotomo Kawagoe, P. G. Estabrooks, R. K. Keeler, T. Behnke, A. M. Lee, N. K. Watson, W. J. McDonald, P. M. Watkins, John Allison, E. von Törne, K. R. Hossain, D. Chrisman, G. D. Long, Volker Blobel, S. W. O'Neale, K. J. Anderson, Stephen Lloyd, T. J. McMahon, R. G. Kellogg, A. Macchiolo, M. Gruwé, C. M. Hawkes, C. Dallapiccola, B. C. Shen, Siegfried Bethke, A. K. Honma, W. G. Scott, I. Nakamura, P. E.L. Clarke, M. K. Jones, J. P. Martin, C. Hartmann, R. K. Carnegie, M. Herndon, M. Bobinski, J. A. Wilson, Csaba Hajdu, Richard Teuscher, A. S. Turcot, Stefano Marcellini, F. Fiedler, U. Müller, A. J. Martin, J. Letts, M. Fanti, P. Poffenberger, M. Fierro, J. E.G. Edwards, B. Stockhausen, Paul Kyberd, F. K. Loebinger, R. Davis, Silvia Arcelli, M. Schumacher, E. Lefebvre, Richard Nisius, U. Ruppel, M. R. Ingram, D. E. Plane, Stephen Hillier, D. Glenzinski, G. M. Dallavalle, Dezso Horvath, M. J. Losty, S. De Jong, O. C. Cooke, P. Pfeifenschneider, D. Lazic, J. Steuerer, Ivor Fleck, Joleen Pater, K. Sachs, Shlomo Dado, Robert McPherson, F. Odorici, J. Patt, Beatrix Dienes, G. Yekutieli, A. Klier, R. Giacomelli, A. Oh, C. K. Hargrove, Ekg Sarkisyan, P. W. Jeffreys, S. Baumann, E. A. Mckigney, W. P. Lai, Marco Cuffiani, Mathieu Doucet, R. D. Heuer, Tara Shears, Jean-Arcady Meyer, A. Schüning, A. N. Bell, P. S. Wells, S. Yamashita, P. Igo-Kemenes, M. Boutemeur, F. S. Merritt, A. A. Carter, Ron Folman, Gideon Alexander, James Pinfold, Paolo Capiluppi, R. Perez-Ochoa, D. G. Fong, Fabrizio Fabbri, J. M. Roney, R. Van Kooten, P. A. Hart, J. Gascon, N. Altekamp, H. Voss, Ehud Duchovni, R. J. Barlow, M. Jimack, Terry Richard Wyatt, K. Ishii, Paolo Giacomelli, H. Jeremie, J. E. Bloomer, M. Hansroul, A. Michelini, P. Müttig, M. Kolrep, Giora Mikenberg, P. Utzat, Satoshi Tanaka, T. Kobayashi, M. J. Pearce, D. I. Futyan, M. Hapke, C. Burgard, C. Y. Chang, R. J. Homer, A. Macpherson, Satoshi Mihara, G. G. Hanson, Gideon Bella, Daniele Bonacorsi, D. J. Miller, S. Braibant, A. D. Schaile, Gabriella Pasztor, M. A. Thomson, H. Mes, I. P. Duerdoth, P. Taras, Michael Kobel, F. Wäckerle, P. Vikas, J. von Krogh, D. Lanske, J. W. Gary, A. Joly, Reda Tafirout, Klaus Kurt Desch, M. Thiergen, O. Schaile, S. B. Anderson, E. do Couto e Silva, P. Szymanski, H. J. Burckhart, Jacqueline Batley, R. Howard, J. Grunhaus, Claire Shepherd-Themistocleous, J. S. White, E. K. U. Gross, G. W. Wilson, D. S. Koetke, Marcello Mannelli, D. M. Gingrich, C. Sbarra, J. Bechtluft, U. Jost, R. Mir, Allen Mincer, Stan Bentvelsen, G. Giacomelli, J. A. McKenna, G. A. Snow, C. P. Ward, D. E. Hutchcroft, M. J. Oreglia, Julie Kirk, P. Hüntemeyer, P. Scharff-Hansen, M. S. Dixit, L. A. del Pozo, S. R. Lautenschlager, H. A. Neal, Frans Meijers, M. Sproston, Sven Menke, K. Stephens, S. Söldner-Rembold, D. M. Strom, M. Hauschild, R. Hawkings, C. Markus, P. Gagnon, A. A. Faust, R. Rylko, A. M. Smith, Hans-Christian Schultz-Coulon, Randall Sobie, G. D. Lafferty, O. Runolfsson, W. R. Gibson, A. Biguzzi, R. Bartoldus, H. O. Ogren, Christoph Geich-Gimbel, S. M. Gascon-Shotkin, B. T. Bouwens, G. T. Jones, E. H. Vokurka, K. Stoll, Andris Skuja, S. Petzold, C. R. Jones, R. M. Brown, Tetsuro Mashimo, Lorne Levinson, F. G. Oakham, C. Beeston, B. Schmitt, Vakhtang Kartvelishvili, A. Skillman, V. Gibson, E. L. Barberio, A. Rooke, J. G. Layter, Guenter Duckeck, J. E. Conboy, A. Fürtjes, J. R. Carter, W. Gorn, Claudio Grandi, M. Schrüder, D. Rigby, R. J. Hemingway, D. L. Rees, G. N. Patrick, B. W. Kennedy, T. R. Junk, Dave Charlton, P. Jovanovic, Austin Ball, F. Scharf, Otmar Biebel, M. F. Turner-Watson, M. Morii, Peter Krieger, Peter R Hobson, S. Robertson, Gregor Herten, B. Wilkens, German Martinez, Alessandro Montanari, D. Zer-Zion, P. Routenburg, I. Trigger, R. Bürgin, Sachio Komamiya, Theodoros Geralis, E. Ros, A. T. Watson, J. E. Pilcher, D. R. Ward, T. Kress, J. Schieck, W. Mohr, A. Sittler, T. P. Kokott, A. Posthaus, T. Saeki, P. I. Kayal, N. J. Oldershaw, Peter Schleper, Zoltan Laszlo Trocsanyi, Norbert Wermes, Sherry Towers, T. Kawamoto, S. Orito, S. D. Bird, P. Schenk, D. Axen, A. Jawahery, Matthew Evans, Peter Sherwood, Alexander Wagner, A. M. Rossi, J. Ludwig, K. Runge, P. Bock, J. Lauber, H. M. Fischer, S. D. Talbot, D. Eatough, N. I. Geddes, Michael Hildreth, N. L. Rodning, B. Poli, R. W. Springer, Georges Azuelos, E. Tsur, M. Verzocchi, K. W. Bell, J. Pálinkás, J. C. Hill, S. A. Robins, Gunter Wolf, K. Ackerstaff, I. J. Bloodworth, Yoram Rozen, R. Lahmann, D. C. Imrie, M. Foucher, Stefan Kluth, Shlomit Tarem, G. P. Siroli, J. Goldberg, B. Nellen, Christoph Schwick, H. G. Evans, D. Karlen, M. J. Goodrick, I. Cohen, Daniel Lellouch, Takehiko Mori, V. Zacek, Stefan Schmitt, Shoji Asai, and K. Nagai
Subjects: Physics, Particle physics, E+E ANNIHILATION, Physics and Astronomy (miscellaneous), ENERGIES, Electron–positron annihilation, Scalar (mathematics), P(P)OVER-BAR COLLISIONS, Lower limit, PARAMETERS, OPAL DETECTOR, CROSS-SECTIONS, Nuclear physics, PHYSICS, Pair production, Chargino, SUPERSYMMETRIC PARTICLES, Neutralino, MONTE-CARLO PROGRAM, TEV, Engineering (miscellaneous), Minimal Supersymmetric Standard Model
Abstract: A search for charginos and neutralinos, predicted by supersymmetric theories, is performed using a data sample of 182.1 pb-1 taken at a centre-of-mass energy of 189 GeV with the OPAL detector at LEP. No evidence for chargino or neutralino production is found. Upper limits on chargino and neutralino pair production (X1+X1-, X10X20) cross-sections are obtained as a function of the chargino mass (mX1±), the lightest neutralino mass (mX10) and the second lightest neutralino mass (mX20). Within the Constrained Minimal Supersymmetric Standard Model framework, and for mX1± - mX10 ≥ 5 GeV, the 95% confidence level lower limits on mX1± are 93.6 GeV for tan β = 1.5 and 94.1 GeV for tan β = 35. These limits are obtained assuming a universal scalar mass m0 ≥ 500 GeV. The corresponding limits for all m0 are 78.0 and 71.7 GeV. The 95% confidence level lower limits on the lightest neutralino mass, valid for any value of tan β are 32.8 GeV for m0 ≥ 500 GeV and 31.6 GeV for all m0.
Published: 1998

49. Search for stable and long-lived massive charged particles in e(+)e(-) collisions at root s=130-183 GeV

Author: K Ackerstaff, G Alexander, J Allison, N Altekamp, K.J Anderson, S Anderson, S Arcelli, S Asai, S.F Ashby, D Axen, G Azuelos, A.H Ball, E Barberio, R.J Barlow, R Bartoldus, J.R Batley, S Baumann, J Bechtluft, T Behnke, K.W Bell, G Bella, S Bentvelsen, S Bethke, S Betts, O Biebel, A Biguzzi, S.D Bird, V Blobel, I.J Bloodworth, M Bobinski, P Bock, D Bonacorsi, M Boutemeur, S Braibant, L Brigliadori, R.M Brown, H.J Burckhart, C Burgard, R Bürgin, P Capiluppi, R.K Carnegie, A.A Carter, J.R Carter, C.Y Chang, D.G Charlton, D Chrisman, P.E.L Clarke, I Cohen, J.E Conboy, O.C Cooke, C Couyoumtzelis, R.L Coxe, M Cuffiani, S Dado, C Dallapiccola, G.M Dallavalle, R Davis, S De Jong, L.A del Pozo, A de Roeck, K Desch, B Dienes, M.S Dixit, M Doucet, E Duchovni, G Duckeck, I.P Duerdoth, D Eatough, P.G Estabrooks, E Etzion, H.G Evans, M Evans, F Fabbri, A Fanfani, M Fanti, A.A Faust, L Feld, F Fiedler, M Fierro, H.M Fischer, I Fleck, R Folman, D.G Fong, M Foucher, A Fürtjes, D.I Futyan, P Gagnon, J.W Gary, J Gascon, S.M Gascon-Shotkin, N.I Geddes, C Geich-Gimbel, T Geralis, G Giacomelli, P Giacomelli, R Giacomelli, V Gibson, W.R Gibson, D.M Gingrich, D Glenzinski, J Goldberg, M.J Goodrick, W Gorn, C Grandi, E Gross, J Grunhaus, M Gruwé, C Hajdu, G.G Hanson, M Hansroul, M Hapke, C.K Hargrove, P.A Hart, C Hartmann, M Hauschild, C.M Hawkes, R Hawkings, R.J Hemingway, M Herndon, G Herten, R.D Heuer, M.D Hildreth, J.C Hill, S.J Hillier, P.R Hobson, A Hocker, R.J Homer, A.K Honma, D Horváth, K.R Hossain, R Howard, P Hüntemeyer, D.E Hutchcroft, P Igo-Kemenes, D.C Imrie, K Ishii, A Jawahery, P.W Jeffreys, H Jeremie, M Jimack, A Joly, C.R Jones, M Jones, U Jost, P Jovanovic, T.R Junk, J Kanzaki, D Karlen, V Kartvelishvili, K Kawagoe, T Kawamoto, P.I Kayal, R.K Keeler, R.G Kellogg, B.W Kennedy, J Kirk, A Klier, S Kluth, T Kobayashi, M Kobel, D.S Koetke, T.P Kokott, M Kolrep, S Komamiya, R.V Kowalewski, T Kress, P Krieger, J von Krogh, P Kyberd, G.D Lafferty, R Lahmann, W.P Lai, D Lanske, J Lauber, S.R Lautenschlager, I Lawson, J.G Layter, D Lazic, A.M Lee, E Lefebvre, D Lellouch, J Letts, L Levinson, B List, S.L Lloyd, F.K Loebinger, G.D Long, M.J Losty, J Ludwig, D Lui, A Macchiolo, A Macpherson, M Mannelli, S Marcellini, C Markopoulos, C Markus, A.J Martin, J.P Martin, G Martinez, T Mashimo, P Mättig, W.J McDonald, J McKenna, E.A Mckigney, T.J McMahon, R.A McPherson, F Meijers, S Menke, F.S Merritt, H Mes, J Meyer, A Michelini, S Mihara, G Mikenberg, D.J Miller, A Mincer, R Mir, W Mohr, A Montanari, T Mori, K Nagai, I Nakamura, H.A Neal, B Nellen, R Nisius, S.W O'Neale, F.G Oakham, F Odorici, H.O Ogren, A Oh, N.J Oldershaw, M.J Oreglia, S Orito, J Pálinkás, G Pásztor, J.R Pater, G.N Patrick, J Patt, R Perez-Ochoa, S Petzold, P Pfeifenschneider, J.E Pilcher, J Pinfold, D.E Plane, P Poffenberger, B Poli, A Posthaus, C Rembser, S Robertson, S.A Robins, N Rodning, J.M Roney, A Rooke, A.M Rossi, P Routenburg, Y Rozen, K Runge, O Runolfsson, U Ruppel, D.R Rust, K Sachs, T Saeki, O Sahr, W.M Sang, E.K.G Sarkisyan, C Sbarra, A.D Schaile, O Schaile, F Scharf, P Scharff-Hansen, J Schieck, P Schleper, B Schmitt, S Schmitt, A Schöning, M Schröder, M Schumacher, C Schwick, W.G Scott, T.G Shears, B.C Shen, C.H Shepherd-Themistocleous, P Sherwood, G.P Siroli, A Sittler, A Skillman, A Skuja, A.M Smith, G.A Snow, R Sobie, S Söldner-Rembold, R.W Springer, M Sproston, K Stephens, J Steuerer, B Stockhausen, K Stoll, D Strom, R Ströhmer, P Szymanski, R Tafirout, S.D Talbot, P Taras, S Tarem, R Teuscher, M Thiergen, M.A Thomson, E von Törne, E Torrence, S Towers, I Trigger, Z Trócsányi, E Tsur, A.S Turcot, M.F Turner-Watson, I Ueda, P Utzat, R Van Kooten, P Vannerem, M Verzocchi, P Vikas, E.H Vokurka, H Voss, F Wäckerle, A Wagner, C.P Ward, D.R Ward, P.M Watkins, A.T Watson, N.K Watson, P.S Wells, N Wermes, J.S White, G.W Wilson, J.A Wilson, T.R Wyatt, S Yamashita, G Yekutieli, V Zacek, and D Zer-Zion
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Range (particle radiation), Muon, 010308 nuclear & particles physics, Detector, Scalar (mathematics), Charge (physics), 01 natural sciences, Electric charge, Charged particle, 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Particle Physics - Experiment, Lepton
Abstract: A search for stable and long-lived massive particles of electric charge |Q/e| = 1 or 2/3, pair-produced in e+e- collisions at centre-of-mass energies from 130 to 183 GeV, is reported by the OPAL collaboration at LEP. No evidence for production of these particles was observed in a mass range between 45 and 89.5 GeV. Model-independent upper limits on the production cross-section between 0.05 and 0.19 pb have been derived for scalar and spin-1/2 particles with charge +/-1. Within the framework of the minimal supersymmetric model (MSSM), this implies a lower limit of 82.5 (83.5) GeV on the mass of long-lived right- (left-)handed scalar muons and scalar taus. Long-lived charged leptons and charginos are excluded for masses below 89.5 GeV. For particles with charge +/-2/3 the upper limits on the production cross-section vary between 0.05 and 0.2 pb. All limits, on masses and on cross-sections, are valid at the 95% confidence level for particles with lifetimes longer than 10^{-6} s. A search for stable and long-lived massive particles of electric charge |Q/e| = 1 or 2/3, pair-produced in e+e- collisions at centre-of-mass energies from 130 to 183 GeV, is reported by the OPAL collaboration at LEP. No evidence for production of these particles was observed in a mass range between 45 and 89.5 GeV. Model-independent upper limits on the production cross-section between 0.05 and 0.19 pb have been derived for scalar and spin-1/2 particles with charge +/-1. Within the framework of the minimal supersymmetric model (MSSM), this implies a lower limit of 82.5 (83.5) GeV on the mass of long-lived right- (left-)handed scalar muons and scalar taus. Long-lived charged leptons and charginos are excluded for masses below 89.5 GeV. For particles with charge +/-2/3 the upper limits on the production cross-section vary between 0.05 and 0.2 pb. All limits, on masses and on cross-sections, are valid at the 95% confidence level for particles with lifetimes longer than 10^{-6} s. A search for stable and long-lived massive particles of electric charge |Q/e| = 1 or 2/3, pair-produced in e+e- collisions at centre-of-mass energies from 130 to 183 GeV, is reported by the OPAL collaboration at LEP. No evidence for production of these particles was observed in a mass range between 45 and 89.5 GeV. Model-independent upper limits on the production cross-section between 0.05 and 0.19 pb have been derived for scalar and spin-1/2 particles with charge +/-1. Within the framework of the minimal supersymmetric model (MSSM), this implies a lower limit of 82.5 (83.5) GeV on the mass of long-lived right- (left-)handed scalar muons and scalar taus. Long-lived charged leptons and charginos are excluded for masses below 89.5 GeV. For particles with charge +/-2/3 the upper limits on the production cross-section vary between 0.05 and 0.2 pb. All limits, on masses and on cross-sections, are valid at the 95% confidence level for particles with lifetimes longer than 10^{-6} s. A search for stable and long-lived massive particles of electric charge |Q/e| = 1 or 2/3, pair-produced in e+e- collisions at centre-of-mass energies from 130 to 183 GeV, is reported by the OPAL collaboration at LEP. No evidence for production of these particles was observed in a mass range between 45 and 89.5 GeV. Model-independent upper limits on the production cross-section between 0.05 and 0.19 pb have been derived for scalar and spin-1/2 particles with charge +/-1. Within the framework of the minimal supersymmetric model (MSSM), this implies a lower limit of 82.5 (83.5) GeV on the mass of long-lived right- (left-)handed scalar muons and scalar taus. Long-lived charged leptons and charginos are excluded for masses below 89.5 GeV. For particles with charge +/-2/3 the upper limits on the production cross-section vary between 0.05 and 0.2 pb. All limits, on masses and on cross-sections, are valid at the 95% confidence level for particles with lifetimes longer than 10^{-6} s. A search for stable and long-lived massive particles of electric charge | Q / e |=1 or 2/3, pair-produced in e + e − collisions at centre-of-mass energies from 130 to 183 GeV, is reported by the OPAL collaboration at LEP. No evidence for production of these particles was observed in a mass range between 45 and 89.5 GeV. Model-independent upper limits on the production cross-section between 0.05 and 0.19 pb have been derived for scalar and spin-1/2 particles with charge ±1. Within the framework of the minimal supersymmetric model (MSSM), this implies a lower limit of 82.5 (83.5) GeV on the mass of long-lived right- (left-)handed scalar muons and scalar taus. Long-lived charged leptons and charginos are excluded for masses below 89.5 GeV. For particles with charge ±2/3 the upper limits on the production cross-section vary between 0.05 and 0.2 pb. All limits, on masses and on cross-sections, are valid at the 95% confidence level for particles with lifetimes longer than 10 −6 s.
Published: 1998

50. W+W- production and triple gauge boson couplings at LEP energies up to 183 GeV

Author: Abbiendi, G., Ackerstaff, K., Alexander, G., Allison, John, Altekamp, N., Anderson, K.J., Anderson, S., Arcelli, S., Asai, S., Ashby, S.F., Axen, D., Azuelos, G., Ball, A.H., Barberio, E., Barlow, Roger J., Bartoldus, R., Batley, J.R., Baumann, S., Bechtluft, J., Behnke, T., Bell, Kenneth Watson, Bella, G., Bellerive, A., Bentvelsen, S., Bethke, S., Betts, S., Biebel, O., Biguzzi, A., Bird, S.D., Blobel, V., Bloodworth, I.J., Bock, P., Bohme, J., Bonacorsi, D., Boutemeur, M., Braibant, S., Bright-Thomas, P., Brigliadori, L., Brown, Robert M., Burckhart, H.J., Capiluppi, P., Carnegie, R.K., Carter, A.A., Carter, J.R., Chang, C.Y., Charlton, David G., Chrisman, D., Ciocca, C., Clarke, P.E.L., Clay, E., Cohen, I., Conboy, J.E., Cooke, O.C., Couyoumtzelis, C., Coxe, R.L., Cuffiani, M., Dado, S., Dallavalle, G.Marco, Davis, R., De Jong, S., De Roeck, A., Dervan, P., Desch, K., Dienes, B., Dixit, M.S., Dubbert, J., Duchovni, E., Duckeck, G., Duerdoth, I.P., Eatough, D., Estabrooks, P.G., Etzion, E., Fabbri, F., Fanti, M., Faust, A.A., Fiedler, F., Fierro, M., Fleck, I., Folman, R., Furtjes, A., Futyan, D.I., Gagnon, P., Gary, J.W., Gascon, J., Gascon-Shotkin, S.M., Gaycken, G., Geich-Gimbel, C., Giacomelli, G., Giacomelli, P., Gibson, V., Gibson, W.R., Gingrich, D.M., Glenzinski, D., Goldberg, J., Gorn, W., Grandi, C., Graham, K., Gross, E., Grunhaus, J., Gruwe, M., Hanson, G.G., Hansroul, M., Hapke, M., Harder, K., Harel, A., Hargrove, C.K., Hartmann, C., Hauschild, M., Hawkes, C.M., Hawkings, R., Hemingway, R.J., Herndon, M., Herten, G., Heuer, R.D., Hildreth, M.D., Hill, J.C., Hobson, P.R., Hoch, M., Hocker, James Andrew, Hoffman, Kara Dion, Homer, R.J., Honma, A.K., Horvath, D., Hossain, K.R., Howard, R., Huntemeyer, P., Igo-Kemenes, P., Imrie, D.C., Ishii, K., Jacob, F.R., Jawahery, A., Jeremie, H., Jimack, M., Jones, C.R., Jovanovic, P., Junk, T.R., Karlen, D., Kartvelishvili, V., Kawagoe, K., Kawamoto, T., Kayal, P.I., Keeler, R.K., Kellogg, R.G., Kennedy, B.W., Kim, D.H., Klier, A., Kluth, S., Kobayashi, T., Kobel, M., Koetke, D.S., Kokott, T.P., Kolrep, M., Komamiya, S., Kowalewski, Robert V., Kress, T., Krieger, P., von Krogh, J., Kuhl, T., Kyberd, P., Lafferty, G.D., Landsman, H., Lanske, D., Lauber, J., Lautenschlager, S.R., Lawson, I., Layter, J.G., Lazic, D., Lee, A.M., Lellouch, D., Letts, J., Levinson, L., Liebisch, R., List, B., Littlewood, C., Lloyd, A.W., Lloyd, S.L., Loebinger, F.K., Long, G.D., Losty, M.J., Ludwig, J., Lui, D., Macchiolo, A., Macpherson, A., Mader, W., Mannelli, M., Marcellini, S., Markopoulos, C., Martin, A.J., Martin, J.P., Martinez, G., Mashimo, T., Mattig, Peter, McDonald, W.John, McKenna, J., Mckigney, E.A., McMahon, T.J., McPherson, R.A., Meijers, F., Menke, S., Merritt, F.S., Mes, H., Meyer, J., Michelini, A., Mihara, S., Mikenberg, G., Miller, D.J., Mir, R., Mohr, W., Montanari, A., Mori, T., Nagai, K., Nakamura, I., Neal, H.A., Nellen, B., Nisius, R., O'Neale, S.W., Oakham, F.G., Odorici, F., Ogren, H.O., Oreglia, M.J., Orito, S., Palinkas, J., Pasztor, G., Pater, J.R., Patrick, G.N., Patt, J., Perez-Ochoa, R., Petzold, S., Pfeifenschneider, P., Pilcher, J.E., Pinfold, J., Plane, David E., Poffenberger, P., Polok, J., Przybycien, M., Rembser, C., Rick, H., Robertson, S., Robins, S.A., Rodning, N., Roney, J.M., Roscoe, K., Rossi, A.M., Rozen, Y., Runge, K., Runolfsson, O., Rust, D.R., Sachs, K., Saeki, T., Sahr, O., Sang, W.M., Sarkisian, E.K.G., Sbarra, C., Schaile, A.D., Schaile, O., Scharf, F., Scharff-Hansen, P., Schieck, J., Schmitt, B., Schmitt, S., Schoning, A., Schroder, Matthias, Schumacher, M., Schwick, C., Scott, W.G., Seuster, R., Shears, T.G., Shen, B.C., Shepherd-Themistocleous, C.H., Sherwood, P., Siroli, G.P., Sittler, A., Skuja, A., Smith, A.M., Snow, G.A., Sobie, R., Soldner-Rembold, S., Spagnolo, S., Sproston, M., Stahl, A., Stephens, K., Steuerer, J., Stoll, K., Strom, David M., Strohmer, R., Surrow, B., Talbot, S.D., Tanaka, S., Taras, P., Tarem, S., Teuscher, R., Thiergen, M., Thomas, J., Thomson, M.A., von Torne, E., Torrence, E., Towers, S., Trigger, I., Trocsanyi, Z., Tsur, E., Turcot, A.S., Turner-Watson, M.F., Ueda, I., Vachon, B., Van Kooten, Rick J., Vannerem, P., Verzocchi, M., Voss, H., Wackerle, F., Wagner, A., Ward, C.P., Ward, D.R., Watkins, P.M., Watson, A.T., Watson, N.K., Wells, P.S., Wermes, N., White, J.S., Wilson, G.W., Wilson, J.A., Wyatt, T.R., Yamashita, S., Yekutieli, G., Zacek, V., and Zer-Zion, D.
Subjects: Physics, Gauge boson, Particle physics, Luminosity (scattering theory), Physics and Astronomy (miscellaneous), 010308 nuclear & particles physics, Branching fraction, Hadron, FOS: Physical sciences, Fizikai tudományok, Lambda, 7. Clean energy, 01 natural sciences, High Energy Physics - Experiment, Standard Model, High Energy Physics - Experiment (hep-ex), Természettudományok, 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Engineering (miscellaneous), Particle Physics - Experiment, Lepton, Boson
Abstract: A study of W-pair production in e+e- annihilations at Lep2 is presented, based on 877 W+W- candidates corresponding to an integrated luminosity of 57 pb-1 at sqrt(s) = 183 GeV. Assuming that the angular distributions of the W-pair production and decay, as well as their branching fractions, are described by the Standard Model, the W-pair production cross-section is measured to be 15.43 +- 0.61 (stat.) +- 0.26 (syst.) pb. Assuming lepton universality and combining with our results from lower centre-of-mass energies, the W branching fraction to hadrons is determined to be 67.9 +- 1.2 (stat.) +- 0.5 (syst.)%. The number of W-pair candidates and the angular distributions for each final state (qqlnu,qqqq,lnulnu) are used to determine the triple gauge boson couplings. After combining these values with our results from lower centre-of-mass energies we obtain D(kappa_g)=0.11+0.52-0.37, D(g^z_1)=0.01+0.13-0.12 and lambda=-0.10+0.13-0.12, where the errors include both statistical and systematic uncertainties and each coupling is determined setting the other two couplings to the Standard Model value. The fraction of W bosons produced with a longitudinal polarisation is measured to be 0.242+-0.091(stat.)+-0.023(syst.). All these measurements are consistent with the Standard Model expectations., Comment: 48 pages, LaTeX, including 13 eps or ps figures, submitted to European Physical Journal C
Published: 1998
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