Author: "M Thiergen" / Topic: nuclear and high energy physics - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"M Thiergen"' showing total 52 results

Start Over Author "M Thiergen" Topic nuclear and high energy physics

52 results on '"M Thiergen"'

1. Measurement of the B0 lifetime and oscillation frequency using →ℓ decays

Author: G. Abbiendi, K. Ackerstaff, C. Ainsley, P.F. Åkesson, 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, S. Baumann, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, G. Benelli, S. Bentvelsen, S. Bethke, O. Biebel, I.J. Bloodworth, O. Boeriu, P. Bock, J. Böhme, 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, P.E.L. Clarke, E. Clay, I. Cohen, O.C. Cooke, J. Couchman, C. Couyoumtzelis, R.L. Coxe, A. Csilling, M. Cuffiani, S. Dado, G.M. Dallavalle, S. Dallison, A. de Roeck, E. de Wolf, 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, M. Fanti, L. Feld, P. Ferrari, F. Fiedler, I. Fleck, M. Ford, A. Frey, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, D. Glenzinski, J. Goldberg, 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, M. Harin-Dirac, A. Hauke, M. Hauschild, C.M. Hawkes, R. Hawkings, R.J. Hemingway, C. Hensel, G. Herten, R.D. Heuer, J.C. Hill, A. Hocker, K. Hoffman, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, C.R. Jones, P. Jovanovic, T.R. Junk, N. Kanaya, J. Kanzaki, G. Karapetian, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, D.H. Kim, K. Klein, A. Klier, S. Kluth, T. Kobayashi, M. Kobel, T.P. Kokott, 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, 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, W. Menges, F.S. Merritt, H. Mes, 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. Oh, A. Okpara, M.J. Oreglia, S. Orito, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, B. Poli, J. Polok, O. Pooth, M. Przybycień, A. Quadt, C. Rembser, P. Renkel, H. Rick, 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, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, P. Scharff-Hansen, 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, L. Stumpf, B. Surrow, S.D. Talbot, S. Tarem, R.J. Taylor, R. Teuscher, M. Thiergen, J. Thomas, M.A. Thomson, E. Torrence, S. Towers, D. Toya, T. Trefzger, I. Trigger, Z. Trócsányi, E. Tsur, M.F. Turner-Watson, I. Ueda, B. Vachon, P. Vannerem, M. Verzocchi, H. Voss, J. Vossebeld, 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, Meson, 010308 nuclear & particles physics, Oscillation, 0103 physical sciences, Detector, 010306 general physics, 01 natural sciences
Abstract: The lifetime and oscillation frequency of the B0 meson has been measured using B0->D*+l-v decays recorded on the Z0 peak with the OPAL detector at LEP. The D*+ -> D0pi+ decays were reconstructed using an inclusive technique and the production flavour of the B0 mesons was determined using a combination of tags from the rest of the event. The results t_B0 = 1.541 +- 0.028 +- 0.023 ps, Dm_d = 0.497 +- 0.024 +- 0.025 ps-1 were obtained, where in each case the first error is statistical and the second systematic.
Published: 2000

2. First measurement of the inclusive branching ratio of b hadrons to φ mesons in Z decays

Author: G. Abbiendi, K. Ackerstaff, C. Ainsley, 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, S. Baumann, T. Behnke, K.W. Bell, G. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, O. Biebel, 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, 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, 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, M. Fanti, L. Feld, P. Ferrari, F. Fiedler, I. Fleck, M. Ford, A. Frey, A. Fürtjes, D.I. Futyan, P. Gagnon, J.W. Gary, G. Gaycken, C. Geich-Gimbel, G. Giacomelli, P. Giacomelli, D. Glenzinski, J. Goldberg, 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, A. Hocker, K. Hoffman, R.J. Homer, A.K. Honma, D. Horváth, K.R. Hossain, R. Howard, P. Hüntemeyer, P. Igo-Kemenes, K. Ishii, F.R. Jacob, A. Jawahery, H. Jeremie, C.R. Jones, P. Jovanovic, T.R. Junk, N. Kanaya, J. Kanzaki, G. Karapetian, D. Karlen, V. Kartvelishvili, K. Kawagoe, T. Kawamoto, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, D.H. Kim, K. Klein, A. Klier, T. Kobayashi, M. Kobel, T.P. Kokott, 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, 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. Oh, A. Okpara, M.J. Oreglia, S. Orito, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, B. Poli, J. Polok, O. 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, E.K.G. Sarkisyan, C. Sbarra, A.D. Schaile, O. Schaile, P. Scharff-Hansen, S. Schmitt, 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, P. Vannerem, M. Verzocchi, H. Voss, J. Vossebeld, 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, Meson, Branching fraction, High Energy Physics::Phenomenology, Hadron, Detector, High Energy Physics::Experiment, Nuclear Experiment, Production rate
Abstract: The inclusive production rate of phi mesons from the decay of b hadrons produced in Z0 decays was measured to be Br(b->phi+X) = 0.0282+-0.0013(stat.)+-0.0019(syst.), using data collected by the OPAL detector at LEP.
Published: 2000

3. 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

4. Z boson pair production in e+e− collisions at and 189 GeV

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: Quark, Physics, Nuclear and High Energy Physics, Particle physics, Annihilation, 010308 nuclear & particles physics, State (functional analysis), 01 natural sciences, Standard Model, Pair production, 0103 physical sciences, High Energy Physics::Experiment, Nuclear Experiment, 010303 astronomy & astrophysics, Lepton
Abstract: A study of Z boson pair production in e+e- annihilation at center-of-mass energies near 183 GeV and 189 GeV is reported. Final states containing only leptons, (l+l-l+l- and l+l-nu nubar), quark and lepton pairs, (q qbar l+l-, q qbar nu nubar) and the all-hadronic final state (q qbar q qbar) are considered. In all states with at least one Z boson decaying hadronically, q qbar and b bbar final states are considered separately using lifetime and event-shape tags, thereby improving the cross-section measurement. At sqrt(s) = 189 GeV the Z-pair cross section was measured to be 0.80 (+0.14-0.13, stat.) (+0.06-0.05, syst.) pb, consistent with the Standard Model prediction. At sqrt(s) = 183 GeV the 95% C.L. upper limit is 0.55 pb. Limits on anomalous ZZgamma and ZZZ couplings are derived.
Published: 2000

5. 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

6. 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

7. 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

8. A measurement of the τ→ν branching ratio

Author: S. M. Gascon-Shotkin, P. Poffenberger, A. D. Schaile, Gabriella Pasztor, John Allison, G. Gaycken, P. G. Bright-Thomas, J. Lauber, Erez Etzion, G. Yekutieli, A. J. Martin, M. Przybycień, Stefan Kluth, Shlomit Tarem, Beatrix Dienes, M. Schumacher, P. Gagnon, P. Vannerem, S. D. Talbot, A. Sittler, Zoltan Laszlo Trocsanyi, Dong Hee Kim, T. Kress, Daniel Lellouch, R. G. Kellogg, A. M. Rossi, A. A. Carter, Ron Folman, D. Eatough, Takehiko Mori, F. Odorici, B. Surrow, G. A. Snow, C. P. Ward, T. Behnke, W. Mader, Stefano Marcellini, S. D. Bird, P. Mättig, C. K. Hargrove, S. Söldner-Rembold, H. A. Neal, D. Axen, A. Jawahery, M. Fanti, C. Y. Chang, S. A. Robins, P. G. Estabrooks, R. K. Keeler, D. C. Imrie, Dave Charlton, Claire Shepherd-Themistocleous, Peter Sherwood, Alexander Wagner, Giovanni Abbiendi, J. Ludwig, K. Runge, P. Bock, N. K. Watson, Matthias Schröder, P. Taras, Paul Kyberd, F. K. Loebinger, K. Hoffman, R. Liebisch, K. Ackerstaff, J. Steuerer, T. R. Junk, G. P. Siroli, E. Tsur, Ivor Fleck, M. Thiergen, S. R. Lautenschlager, Stefan Schmitt, P. S. Wells, P. M. Watkins, T. J. McMahon, M. Verzocchi, K. W. Bell, Joleen Pater, C. Couyoumtzelis, A. Klier, Christoph Schwick, R. J. Hemingway, J. Pálinkás, S. B. Anderson, M. Boutemeur, F. S. Merritt, A. A. Faust, R. D. Heuer, J. Dubbert, R. K. Carnegie, K. Sachs, M. Herndon, James Pinfold, R. Perez-Ochoa, R. Seuster, Terry Richard Wyatt, J. C. Hill, Robert McPherson, Christopher Hawkes, J. A. Wilson, J. Böhme, Shoji Asai, W. M. Sang, Shlomo Dado, L. Brigliadori, O. Runolfsson, Claudia Ciocca, B. W. Kennedy, P. Jovanovic, Gideon Bella, I. J. Bloodworth, Gregor Herten, W. J. McDonald, B. C. Shen, J. Gascon, S. Baumann, D. Lazic, K. Graham, H. J. Burckhart, Jacqueline Batley, A. Macpherson, Tara Shears, Daniele Bonacorsi, Fabrizio Fabbri, Giora Mikenberg, J. Goldberg, Siegfried Bethke, D. Liu, A. K. Honma, E. A. Mckigney, Austin Ball, Yoram Rozen, J. Bechtluft, J. A. McKenna, Peter Krieger, V. Zacek, Claudio Grandi, W. G. Scott, Michael Hildreth, B. Nellen, Stan Bentvelsen, C. Sbarra, G. Azuelos, F. R. Jacob, S. F. Ashby, I. Nakamura, J. S. White, Ekg Sarkisyan, R. Van Kooten, Kiyotomo Kawagoe, J. E. Pilcher, J. W. Gary, N. L. Rodning, D. S. Koetke, A. Macchiolo, J. von Krogh, S. W. O'Neale, J. Letts, Marcello Mannelli, R. Bartoldus, P. Dervan, J. Polok, D. Karlen, Alessandro Montanari, D. Glenzinski, H. Mes, I. P. Duerdoth, A. W. Lloyd, H. O. Ogren, K. J. Anderson, C. R. Jones, K. Stoll, Andris Skuja, S. Petzold, Dezso Horvath, M. J. Losty, M. Gruwé, D. I. Futyan, Christoph Geich-Gimbel, R. Howard, Jean-Arcady Meyer, G. W. Wilson, Tetsuro Mashimo, T. Kuhl, Richard Nisius, M. F. Turner-Watson, M. Hauschild, C. Markopoulos, F. Wäckerle, S. Braibant, A. Bellerive, B. List, Vakhtang Kartvelishvili, R. Mir, D. M. Gingrich, Randall Sobie, G. D. Lafferty, Marco Cuffiani, J. E. Conboy, A. Fürtjes, K. R. Hossain, W. Gorn, I. Cohen, R. Hawkings, Christoph Rembser, D. Lanske, A. Harel, P. Hüntemeyer, Ikuo Ueda, D. M. Strom, P. Scharff-Hansen, H. Landsman, D. R. Rust, A. M. Smith, Guenter Duckeck, M. Fierro, A. M. Lee, Richard Teuscher, A. S. Turcot, E. von Törne, F. Fiedler, M. Kolrep, F. G. Oakham, B. Schmitt, E. L. Barberio, N. Altekamp, H. Voss, R. J. Barlow, D. J. Miller, S. Spagnolo, S. Yamashita, P. Igo-Kemenes, M. Hoch, K. Ishii, H. Jeremie, O. Schaile, S. Robertson, Sven Menke, Ehud Duchovni, M. Jimack, A. Michelini, Satoshi Tanaka, T. Kobayashi, Peter R Hobson, J. M. Roney, R. L. Coxe, D. Zer-Zion, Sachio Komamiya, A. T. Watson, A. Hocker, Koichi Nagai, J. Schieck, D. Chrisman, G. D. Long, T. P. Kokott, W. Mohr, Volker Blobel, Achim Stahl, T. Saeki, R. Davis, Stephen Lloyd, J. Grunhaus, R. Kowalewski, S. Arcelli, F. Scharf, German Martinez, Juergen Thomas, A. Biguzzi, J. G. Layter, Gideon Alexander, M. A. Thomson, Paolo Capiluppi, P. E.L. Clarke, J. P. Martin, E. K. U. Gross, S. De Jong, H. Rick, M. Sproston, G. G. Hanson, G. Giacomelli, I. Lawson, K. Stephens, A. De Roeck, M. Kobel, C. Littlewood, M. S. Dixit, Frans Meijers, O. C. Cooke, P. Pfeifenschneider, V. Gibson, I. Trigger, D. R. Ward, J. Patt, André Schöning, O. Sahr, Satoshi Mihara, Otmar Biebel, Paolo Giacomelli, M. Hansroul, R. J. Homer, P. I. Kayal, Norbert Wermes, Sherry Towers, T. Kawamoto, W. R. Gibson, S. Orito, K. Harder, S. Betts, M. Hapke, M. J. Oreglia, J. R. Carter, G. N. Patrick, R. M. Brown, Lorne Levinson, C. Hartmann, D. E. Plane, G. M. Dallavalle, K. Roscoe, Klaus Kurt Desch, E. Torrence, E. Clay, and Raimund Ströhmer
Subjects: Nuclear physics, Physics, Nuclear and High Energy Physics, Electron energy spectrum, 010308 nuclear & particles physics, Branching fraction, Electron–positron annihilation, 0103 physical sciences, Strong coupling, Analytical chemistry, Mass scale, 010306 general physics, 01 natural sciences
Abstract: The branching ratio for the decay τ − → e − ν e ν τ has been measured using Z 0 decay data collected by the OPAL experiment at LEP. In total 33 073 τ − → e − ν e ν τ candidates were identified from a sample of 186 197 selected τ decays, giving a branching ratio of B (τ − → e − ν e ν τ )=(17.81±0.09 (stat) ±0.06 (syst) )% . This result is combined with other measurements to test e - μ and μ - τ universality in charged-current weak interactions. Additionally, the strong coupling constant α s ( m τ 2 ) has been extracted from B (τ − → e − ν e ν τ ) and evolved to the Z 0 mass scale, giving α s ( m Z 2 )=0.1204±0.0011 (exp)±0.0019 (theory).
Published: 1999

9. 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

10. 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

11. 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

12. 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

13. 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

14. 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

15. 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

16. 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

17. Search for unstable neutral and charged heavy leptons in e+e− collisions at =164

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

18. 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

19. Photonic events with large missing energy in e+e− collisions at

Author: T. P. Kokott, A. Joly, Silvia Arcelli, C. Dallapiccola, C. Sbarra, P. Poffenberger, U. Ruppel, M. R. Ingram, N. Altekamp, E. A. Mckigney, R. J. Barlow, K. Nagai, W. P. Lai, Paolo Giacomelli, M. Hansroul, D. J. Miller, G. Yekutieli, J. Grunhaus, C. Burgard, P. Schütz, U. Jost, R. Mir, Gideon Bella, K. Sachs, J. M. Roney, S. R. Lautenschlager, R. J. Homer, Shlomo Dado, John Allison, R. G. Kellogg, M. Steiert, Csaba Hajdu, Stefano Marcellini, A. A. Carter, H. J. Burckhart, H. A. Neal, Ron Folman, Roger Jones, Jacqueline Batley, Tara Shears, T. Hilse, P. Schenk, M. Hapke, B. Stockhausen, Paul Kyberd, F. K. Loebinger, D. L. Rees, J. Steuerer, F. G. Oakham, B. Schmitt, Joleen Pater, Achim Stahl, O. Runolfsson, R. Giacomelli, G. Azuelos, F. Scharf, T. Omori, D. R. Rust, B. J. King, P. Utzat, P. A. Hart, E. L. Barberio, P. G. Estabrooks, Giora Mikenberg, R. K. Keeler, D. E. Hutchcroft, P. S. Wells, A. Rooke, German Martinez, H. M. Fischer, C. Beeston, Claudio Grandi, W. R. Gibson, J. G. Layter, S. Yamashita, T. J. McMahon, P. Igo-Kemenes, P. M. Watkins, M. J. Oreglia, A. M. Lee, A. S. Turcot, F. Fiedler, M. J. Pearce, G. W. Wilson, C. R. Jones, R. K. Carnegie, K. Ishii, H. Jeremie, W. Matthews, Claire Shepherd-Themistocleous, H. Mes, I. P. Duerdoth, M. Boutemeur, F. S. Merritt, S. W. O'Neale, K. J. Anderson, M. F. Turner-Watson, J. R. Carter, G. N. Patrick, E. von Törne, D. Rigby, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, P. Pfeifenschneider, P. Fath, S. Braibant, A. D. Schaile, Gabriella Pasztor, M. Morii, M. Herndon, M. Bobinski, J. A. Wilson, M. Hauschild, S. A. Wotton, C. Markus, R. E. Hughes-Jones, Peter R Hobson, P. Routenburg, O. Schaile, T. J. Smith, K. Stephens, Terry Richard Wyatt, J. E. Bloomer, Austin Ball, Peter Krieger, Manuella Vincter, Alessandro Montanari, J. Patt, Dave Charlton, Otmar Biebel, J. Bechtluft, M. A. Thomson, S. A. Robins, R. Lahmann, A. Buguzzi, J. A. McKenna, D. C. Imrie, U. Müller, A. J. Martin, G. A. Snow, C. P. Ward, G. T. Jones, E. H. Vokurka, B. T. Bouwens, R. M. Brown, Lorne Levinson, E. do Couto e Silva, D. Lazic, P. E.L. Clarke, M. K. Jones, R. Bürgin, E. K. U. Gross, M. Sproston, S. Söldner-Rembold, M. Fierro, J. E.G. Edwards, D. Chrisman, Sven Menke, J. P. Martin, T. Behnke, V. Gibson, O. C. Cooke, Ekg Sarkisyan, P. W. Jeffreys, N. J. Oldershaw, R. Bartoldus, M. Kolrep, T. R. Junk, S. De Jong, I. Trigger, H. O. Ogren, A. Skillman, Volker Blobel, J. Letts, Christoph Geich-Gimbel, Norbert Wermes, Sherry Towers, M. Gruwé, C. M. Hawkes, D. R. Ward, T. Kress, J. von Krogh, M. Schumacher, T. Kawamoto, C. Hartmann, G. P. Siroli, Hans-Christian Schultz-Coulon, Robert McPherson, D. E. Plane, C. K. Hargrove, Randall Sobie, Michael Schulz, G. D. Lafferty, E. Lefebvre, H. Przysiezniak, N. K. Watson, R. J. Hawkings, S. Orito, M. Rosvick, Mathieu Doucet, Stephen Hillier, Matthias Schröder, L. A. del Pozo, R. D. Heuer, Richard Nisius, Fabrizio Fabbri, G. M. Dallavalle, Stephen Lloyd, F. Odorici, A. N. Bell, J. J. Ward, P. Vikas, M. Thiergen, Marco Cuffiani, J. E. Conboy, A. Fürtjes, N. I. Geddes, Michael Hildreth, D. Lanske, Guenter Duckeck, R. Van Kooten, W. Mohr, D. M. Gingrich, Ehud Duchovni, D. M. Strom, N. L. Rodning, A. Posthaus, S. B. Anderson, Kiyotomo Kawagoe, P. Szymanski, B. Poli, M. Jimack, Stan Bentvelsen, F. Wäckerle, S. Robertson, Gregor Herten, R. Rylko, G. G. Hanson, A. Michelini, B. Wilkens, Reda Tafirout, Klaus Kurt Desch, J. E. Pilcher, Satoshi Tanaka, T. Kobayashi, S. M. Gascon-Shotkin, G. Giacomelli, P. Berlich, Matthew Evans, R. Howard, J. S. White, A. M. Rossi, T. Tsukamoto, M. S. Dixit, Frans Meijers, Andris Skuja, S. Petzold, K. Ametewee, Gideon Alexander, G. D. Long, Paolo Capiluppi, Tetsuro Mashimo, W. Gorn, P. Scharff-Hansen, A. M. Smith, James Pinfold, D. G. Fong, C. Lewis, J. Gascon, J. W. Gary, D. S. Koetke, Marcello Mannelli, R. W. Springer, C. Y. Chang, P. Taras, Michael Kobel, Julie Kirk, E. Tsur, M. Verzocchi, K. W. Bell, J. Pálinkás, J. C. Hill, Misao Sasaki, W. J. McDonald, B. C. Shen, Siegfried Bethke, A. K. Honma, B. Nijjhar, W. G. Scott, I. Nakamura, D. Axen, A. Jawahery, Peter Sherwood, Alexander Wagner, J. Ludwig, K. Runge, P. Bock, J. Lauber, F. Strumia, S. D. Talbot, P. Gagnon, A. Sittler, D. Glenzinski, H. M. Bosch, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, Gunter Wolf, K. Ackerstaff, Stefan Kluth, Shlomit Tarem, A. I. McNab, J. Goldberg, B. Nellen, I. J. Bloodworth, H. G. Evans, M. J. Goodrick, I. Cohen, Yoram Rozen, M. Foucher, D. Karlen, Stefan Schmitt, P. Mättig, Shoji Asai, Daniel Lellouch, Takehiko Mori, V. Zacek, Sachio Komamiya, Theodoros Geralis, E. Ros, and A. T. Watson
Subjects: Nuclear physics, Physics, Nuclear and High Energy Physics, Particle physics, Photon, Luminosity (scattering theory), Missing energy, Branching fraction, Electron–positron annihilation, High Energy Physics::Experiment, Topology (electrical circuits), Supersymmetry, Standard Model
Abstract: Photonic events with large missing energy have been observed with the OPAL detector at LEP using two search topologies. The first topology looks for events with significant missing energy and at least one photon in |cosθ| 0.2. The second topology looks for events with an acoplanar photon pair where both photons are in |cosθ| < 0.7 and have energy exceeding 1.75 GeV. In the data sample corresponding to an integrated luminosity of 10.0 pb−1, 11 events are selected for the first topology and a cross-section of 1.6 ± 0.5 pb is measured within the kinematic acceptance, consistent with that expected for the Standard Model process e+e− → ννγ(γ). No events are selected for the second topology giving a 95% CL cross-section upper limit of 0.41 pb within the kinematic acceptance. Upper limits on the cross-section times branching ratio for new particle production are also derived.
Published: 1997

20. Measurement of the mass of the W boson in e+e− collisions at =161

Author: J. Grunhaus, Otmar Biebel, S. Braibant, A. D. Schaile, K. Nagai, Ehud Duchovni, M. Jimack, Gabriella Pasztor, D. R. Rust, A. Rooke, A. Michelini, John Allison, Daniel Lellouch, J. Letts, O. C. Cooke, J. G. Layter, G. A. Snow, Takehiko Mori, T. Behnke, K. Ackerstaff, Norbert Wermes, Satoshi Tanaka, T. Kobayashi, A. M. Lee, Sherry Towers, T. Kawamoto, P. Schenk, J. von Krogh, C. P. Ward, R. Lahmann, C. Sbarra, D. C. Imrie, E. von Törne, G. Yekutieli, R. J. Hawkings, Sachio Komamiya, W. Matthews, A. A. Carter, Ron Folman, Roger Jones, R. G. Kellogg, B. J. King, P. Utzat, S. Orito, M. Steiert, S. Söldner-Rembold, V. Zacek, Theodoros Geralis, E. Ros, A. T. Watson, L. A. del Pozo, T. J. McMahon, M. Rosvick, M. A. Thomson, Csaba Hajdu, James Pinfold, M. Gruwé, D. G. Fong, C. Lewis, C. M. Hawkes, P. G. Estabrooks, R. K. Keeler, U. Ruppel, M. R. Ingram, Stefano Marcellini, M. Boutemeur, F. S. Merritt, W. J. McDonald, E. K. U. Gross, N. I. Geddes, Michael Hildreth, J. Gascon, M. Hapke, T. P. Kokott, H. Mes, Richard Nisius, J. Lauber, S. B. Anderson, N. L. Rodning, Gideon Bella, P. Szymanski, G. P. Siroli, P. M. Watkins, M. Sproston, R. Van Kooten, P. E.L. Clarke, D. E. Hutchcroft, Marco Cuffiani, R. K. Carnegie, I. J. Bloodworth, B. C. Shen, M. Herndon, I. P. Duerdoth, M. Bobinski, A. I. McNab, J. Goldberg, J. A. Wilson, H. J. Burckhart, M. K. Jones, B. Poli, J. P. Martin, Jacqueline Batley, M. J. Oreglia, D. Lazic, J. W. Gary, P. Fath, B. Nellen, F. Strumia, S. Yamashita, C. Y. Chang, B. Stockhausen, Paul Kyberd, F. K. Loebinger, S. De Jong, S. D. Talbot, H. M. Fischer, D. S. Koetke, Marcello Mannelli, K. Ametewee, Siegfried Bethke, N. K. Watson, F. Wäckerle, A. K. Honma, J. Steuerer, Paolo Giacomelli, M. Hansroul, K. Sachs, Yoram Rozen, Shlomo Dado, B. Nijjhar, W. G. Scott, J. R. Carter, G. N. Patrick, Silvia Arcelli, P. Taras, Michael Kobel, Gideon Alexander, H. Przysiezniak, T. Omori, Claire Shepherd-Themistocleous, Joleen Pater, P. Igo-Kemenes, J. Bechtluft, H. G. Evans, P. Berlich, Paolo Capiluppi, S. A. Robins, P. Scharff-Hansen, J. A. McKenna, I. Nakamura, M. F. Turner-Watson, Stan Bentvelsen, M. Foucher, R. Giacomelli, M. Morii, Peter R Hobson, K. Ishii, H. Jeremie, P. Routenburg, M. J. Goodrick, I. Cohen, E. A. Mckigney, W. Mohr, Robert McPherson, A. M. Smith, A. N. Bell, M. Schumacher, E. Lefebvre, Giora Mikenberg, A. Posthaus, D. Chrisman, W. P. Lai, Mathieu Doucet, R. D. Heuer, R. E. Hughes-Jones, S. M. Gascon-Shotkin, Volker Blobel, C. Burgard, R. J. Homer, Fabrizio Fabbri, M. Fierro, Andris Skuja, S. Petzold, C. R. Jones, J. E.G. Edwards, D. Glenzinski, Dezso Horvath, M. J. Losty, F. Odorici, G. G. Hanson, G. D. Long, J. M. Roney, Tetsuro Mashimo, D. Karlen, Hans-Christian Schultz-Coulon, Stephen Lloyd, Randall Sobie, Michael Schulz, G. D. Lafferty, S. R. Lautenschlager, Stefan Kluth, Shlomit Tarem, Jean-Arcady Meyer, P. Gagnon, Matthew Evans, H. A. Neal, A. M. Rossi, T. J. Smith, K. Stephens, R. Bartoldus, D. L. Rees, T. Tsukamoto, W. Gorn, A. Joly, G. Giacomelli, F. Scharf, German Martinez, T. Hilse, R. W. Springer, G. W. Wilson, O. Runolfsson, H. O. Ogren, Dave Charlton, P. Pfeifenschneider, V. Gibson, Christoph Geich-Gimbel, Guenter Duckeck, O. Schaile, Stefan Schmitt, T. R. Junk, A. Sittler, C. Beeston, M. Hauschild, R. Bürgin, J. Patt, Claudio Grandi, E. do Couto e Silva, Georges Azuelos, I. Trigger, Ekg Sarkisyan, P. W. Jeffreys, M. S. Dixit, E. Tsur, D. R. Ward, T. Kress, M. Verzocchi, Frans Meijers, K. W. Bell, P. Mättig, J. Pálinkás, Shoji Asai, S. A. Wotton, Kiyotomo Kawagoe, A. S. Turcot, J. J. Ward, F. Fiedler, P. Vikas, J. C. Hill, D. Lanske, Misao Sasaki, Achim Stahl, Sven Menke, H. M. Bosch, M. Kolrep, C. Markus, G. T. Jones, D. Axen, A. Jawahery, J. E. Conboy, A. Fürtjes, E. H. Vokurka, Peter Sherwood, Alexander Wagner, J. Ludwig, K. Runge, P. Bock, N. J. Oldershaw, P. S. Wells, S. Robertson, Gregor Herten, B. Wilkens, J. E. Pilcher, Terry Richard Wyatt, J. E. Bloomer, U. Müller, A. J. Martin, C. K. Hargrove, Tara Shears, P. A. Hart, R. Howard, M. J. Pearce, J. S. White, Reda Tafirout, Klaus Kurt Desch, Matthias Schröder, C. Hartmann, D. E. Plane, Stephen Hillier, M. Thiergen, G. M. Dallavalle, Julie Kirk, W. R. Gibson, D. M. Gingrich, B. T. Bouwens, S. W. O'Neale, K. J. Anderson, R. M. Brown, G. WoIf, Lorne Levinson, P. Poffenberger, A. Skillman, P. Schütz, D. M. Strom, R. Rylko, U. Jost, R. Mir, F. G. Oakham, B. Schmitt, E. L. Barberio, C. Dallapiccola, N. Altekamp, R. J. Barlow, D. J. Miller, D. Rigby, R. J. Hemingway, B. W. Kennedy, P. Jovanovic, Austin Ball, Peter Krieger, Manuella Vincter, and Alessandro Montanari
Subjects: Physics, Nuclear physics, Nuclear and High Energy Physics, Particle physics, Pair production, Luminosity (scattering theory), Electron–positron annihilation, Detector, Beam energy, Energy (signal processing), Standard Model
Abstract: This letter describes the first observation of W boson pair production at a centre-of-mass energy s =161 GeV in the OPAL detector at LEP. The analysis is sensitive to all expected W + W − decay channels. A total of 28 events have been selected for an integrated luminosity of 9.89±0.06 pb −1 . This is consistent with the Standard Model expectation, including signal and background contributions. The W pair production cross-section is measured to be σ WW = 3.62 −0.82 +0.93 ±0.16 pb. An analysis of the predicted M W dependence of the accepted cross-section, taking into account interference in the four-fermion production processes, yields M W = 80.40 −0.41−0.10 +0.44+0.09 ±0.10 GeV, where the first and second uncertainties are statistical and systematic, respectively, and the third arises form the beam energy uncertainty.
Published: 1996

21. Search for chargino and neutralino production in e+e− collisions at = 161

Author: A. Rooke, J. G. Layter, Sachio Komamiya, Theodoros Geralis, I. J. Bloodworth, K. Nagai, E. Ros, A. T. Watson, A. I. McNab, J. Goldberg, Silvia Arcelli, S. R. Lautenschlager, R. Lahmann, D. R. Rust, H. A. Neal, B. Nellen, Otmar Biebel, P. E.L. Clarke, M. K. Jones, J. P. Martin, W. Matthews, S. De Jong, Tara Shears, G. G. Hanson, G. Giacomelli, H. Mes, M. S. Dixit, Frans Meijers, Yoram Rozen, U. Jost, R. Mir, H. Przysiezniak, A. N. Bell, T. Hilse, M. Foucher, M. A. Thomson, T. P. Kokott, I. P. Duerdoth, A. M. Lee, D. M. Strom, P. A. Hart, E. A. Mckigney, H. G. Evans, O. Runolfsson, E. K. U. Gross, Claire Shepherd-Themistocleous, S. Braibant, P. Fath, D. Chrisman, M. J. Goodrick, I. Cohen, E. von Törne, M. Boutemeur, F. S. Merritt, W. P. Lai, R. Rylko, M. Sproston, Volker Blobel, A. D. Schaile, Gabriella Pasztor, D. Karlen, Reda Tafirout, Klaus Kurt Desch, M. J. Pearce, Dave Charlton, J. Letts, F. G. Oakham, C. Beeston, Claudio Grandi, G. P. Siroli, Daniel Lellouch, G. A. Snow, C. P. Ward, Stephen Lloyd, S. Yamashita, B. Schmitt, Stefan Kluth, Norbert Wermes, Sherry Towers, T. Kawamoto, S. W. O'Neale, E. L. Barberio, J. M. Roney, Takehiko Mori, D. C. Imrie, P. Igo-Kemenes, S. Söldner-Rembold, Shlomit Tarem, C. Dallapiccola, J. Bechtluft, K. J. Anderson, R. Bürgin, V. Zacek, P. Scharff-Hansen, N. K. Watson, Robert McPherson, C. Y. Chang, J. A. McKenna, Mathieu Doucet, S. Orito, M. Rosvick, T. Behnke, P. Taras, P. Schenk, K. Ishii, H. Jeremie, R. D. Heuer, Fabrizio Fabbri, U. Müller, Michael Kobel, R. E. Hughes-Jones, N. Altekamp, M. Hapke, Gunter Wolf, P. S. Wells, Terry Richard Wyatt, K. Ackerstaff, R. Van Kooten, A. J. Martin, P. G. Estabrooks, R. K. Keeler, M. Fierro, J. E.G. Edwards, C. Sbarra, R. J. Barlow, A. M. Smith, Stefan Schmitt, Ekg Sarkisyan, P. W. Jeffreys, M. F. Turner-Watson, D. J. Miller, R. Bartoldus, D. E. Hutchcroft, Julie Kirk, J. E. Bloomer, P. Gagnon, Kiyotomo Kawagoe, M. Morii, H. O. Ogren, Gideon Bella, N. J. Oldershaw, W. Mohr, F. Wäckerle, D. M. Gingrich, Christoph Geich-Gimbel, Peter R Hobson, M. Gruwé, G. Yekutieli, M. J. Oreglia, C. K. Hargrove, P. Mättig, J. J. Ward, P. Poffenberger, K. Ametewee, P. Vikas, A. Posthaus, O. Schaile, P. M. Watkins, Shoji Asai, Matthias Schröder, C. M. Hawkes, D. Lanske, Gideon Alexander, C. Hartmann, D. E. Plane, P. Berlich, H. J. Burckhart, A. Sittler, James Pinfold, Paolo Capiluppi, Stephen Hillier, D. Rigby, R. J. Hemingway, R. W. Springer, P. Schütz, M. Thiergen, P. Routenburg, D. G. Fong, C. Lewis, E. do Couto e Silva, A. A. Carter, Ron Folman, Roger Jones, Richard Nisius, J. Gascon, G. M. Dallavalle, J. R. Carter, M. Schumacher, G. N. Patrick, B. W. Kennedy, S. Robertson, Gregor Herten, P. Jovanovic, Jacqueline Batley, B. J. King, E. Lefebvre, P. Utzat, Ehud Duchovni, Marco Cuffiani, B. Wilkens, M. Jimack, D. L. Rees, J. E. Conboy, Austin Ball, A. Fürtjes, J. E. Pilcher, A. Michelini, Peter Krieger, O. C. Cooke, F. Odorici, J. W. Gary, F. Scharf, German Martinez, H. M. Bosch, R. Howard, J. S. White, J. Grunhaus, G. W. Wilson, D. S. Koetke, M. Hauschild, Manuella Vincter, Alessandro Montanari, S. A. Wotton, Satoshi Tanaka, T. Kobayashi, Georges Azuelos, Marcello Mannelli, C. Markus, J. von Krogh, W. R. Gibson, Andris Skuja, E. Tsur, G. T. Jones, Sven Menke, E. H. Vokurka, S. Petzold, G. D. Long, R. J. Hawkings, M. Verzocchi, K. W. Bell, Tetsuro Mashimo, B. T. Bouwens, L. A. del Pozo, J. Pálinkás, A. Joly, H. M. Fischer, T. J. McMahon, T. Omori, D. Axen, J. C. Hill, A. Jawahery, Misao Sasaki, W. J. McDonald, R. K. Carnegie, B. C. Shen, M. Herndon, M. Bobinski, S. A. Robins, W. Gorn, R. M. Brown, Lorne Levinson, J. A. Wilson, T. J. Smith, Siegfried Bethke, K. Stephens, A. K. Honma, B. Nijjhar, W. G. Scott, Peter Sherwood, C. R. Jones, I. Nakamura, D. Lazic, N. I. Geddes, Michael Hildreth, V. Gibson, Alexander Wagner, A. Skillman, N. L. Rodning, B. Poli, J. Ludwig, John Allison, T. R. Junk, K. Runge, P. Bock, I. Trigger, D. R. Ward, T. Kress, J. Lauber, S. M. Gascon-Shotkin, U. Ruppel, M. R. Ingram, D. Glenzinski, Dezso Horvath, Matthew Evans, A. M. Rossi, R. G. Kellogg, T. Tsukamoto, M. Steiert, M. J. Losty, Jean-Arcady Meyer, F. Strumia, S. D. Talbot, Csaba Hajdu, Stefano Marcellini, B. Stockhausen, Paul Kyberd, F. K. Loebinger, J. Steuerer, Joleen Pater, R. Giacomelli, Paolo Giacomelli, M. Hansroul, C. Burgard, R. J. Homer, P. Pfeifenschneider, J. Patt, Achim Stahl, K. Sachs, Shlomo Dado, Giora Mikenberg, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, Guenter Duckeck, A. S. Turcot, F. Fiedler, M. Kolrep, S. B. Anderson, P. Szymanski, and Stan Bentvelsen
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Luminosity (scattering theory), Astrophysics::High Energy Astrophysical Phenomena, Supergravity, High Energy Physics::Phenomenology, Scalar (mathematics), Supersymmetry, Lower limit, Nuclear physics, Chargino, Neutralino, High Energy Physics::Experiment, Nuclear Experiment, Minimal Supersymmetric Standard Model
Abstract: Charginos and neutralinos, predicted by supersymmetric theories, have been searched for in e+e− collisions with an intergrated luminosity of 10.0 pb−1 at a centre-of-mass energy of s = 161 GeV with the OPAL detector at LEP. Two candidate events are selected; consistent with the total background estimate of 0.7 ± 0.2 events. The 95% C.L. lower limit on the lightest chargino mass in the Minimal Supersymmetric Standard Model is 78.5 GeV if the universal scalar mass m0 is greater than 1 TeV, and 62.0 GeV for the smallest m0 compatible with slepton and sneutrino mass limits obtained at centre-of-mass energies near the Z peak. These limits were obtained under the conditions that the lightest chargino is heavier than the lightest neutralino by more than 10 GeV and tan β = 1.5. The new exclusion limits significantly improve on the results obtained at s = 130 and 136 GeV.
Published: 1996

22. Test of QCD analytic predictions for the multiplicity ratio between gluon and quark jets

Author: G. W. Wilson, James Pinfold, M. Hauschild, P. Poffenberger, D. G. Fong, C. Lewis, J. Gascon, S. A. Wotton, C. Markus, P. G. Estabrooks, Stefan Schmitt, P. Schütz, W. J. McDonald, B. C. Shen, D. Rigby, R. J. Hemingway, T. J. Smith, P. Gagnon, S. L. Chu, Siegfried Bethke, G. T. Jones, B. W. Kennedy, P. Jovanovic, Ekg Sarkisyan, P. M. Watkins, A. K. Honma, B. Nijjhar, W. G. Scott, Austin Ball, A. Malik, A. Gaidot, A. Sittler, Paolo Giacomelli, M. Hansroul, I. Nakamura, E. H. Vokurka, M. Hapke, P. Mättig, Shoji Asai, Kiyotomo Kawagoe, J. W. Gary, D. S. Koetke, P. Pfeifenschneider, C. Hartmann, D. E. Plane, J. Patt, Peter Krieger, Marcello Mannelli, C. Burgard, Manuella Vincter, D. M. Strom, Matthias Schröder, H. M. Bosch, D. E. Hutchcroft, I. J. Bloodworth, R. J. Homer, P. W. Jeffreys, Stephen Hillier, M. Boutemeur, F. S. Merritt, Alessandro Montanari, Dave Charlton, H. Mes, M. Thiergen, G. G. Hanson, C. Dallapiccola, S. Braibant, A. D. Schaile, D. Glenzinski, Dezso Horvath, J. Lauber, P. Scharff-Hansen, G. M. Dallavalle, M. J. Oreglia, M. J. Losty, Yoram Rozen, Gabriella Pasztor, P. Weber, I. P. Duerdoth, M. Foucher, Jean-Arcady Meyer, Achim Stahl, R. Bürgin, P. Fath, Silvia Arcelli, T. J. McMahon, T. Behnke, Alan Watson, F. Strumia, S. D. Talbot, R. Rylko, P. Schenk, A. M. Smith, Tara Shears, D. Karlen, J. Bechtluft, G. A. Snow, C. P. Ward, G. Giacomelli, Gideon Bella, C. H. Shepherd-Themistocleous, H. J. Burckhart, S. Söldner-Rembold, N. Altekamp, R. J. Barlow, Jacqueline Batley, G. Vasseur, Stefan Kluth, J. R. Carter, Eilam Gross, R. W. Springer, G. N. Patrick, R. K. Carnegie, M. Bobinski, S. Yamashita, J. A. Wilson, Frank Fiedler, S. W. O'Neale, K. J. Anderson, E. A. Mckigney, J. A. McKenna, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, P. Igo-Kemenes, P. A. Hart, Georges Azuelos, U. Ruppel, M. R. Ingram, M. J. Pearce, M. S. Dixit, E. Tsur, W. P. Lai, C. Y. Chang, M. Gruwé, C. M. Hawkes, Shlomit Tarem, Frans Meijers, B. Stockhausen, Paul Kyberd, F. K. Loebinger, S. M. Gascon-Shotkin, Andris Skuja, K. Ishii, H. Jeremie, Otmar Biebel, T. Omori, R. Bartoldus, Reda Tafirout, Klaus Kurt Desch, D. Lazic, Robert McPherson, P. Taras, M. Verzocchi, K. W. Bell, D. Axen, S. Petzold, A. Jawahery, J. J. Ward, U. Jost, R. Mir, Richard Nisius, Gregor Herten, G. D. Long, R. E. Hughes-Jones, P. Vikas, Tetsuro Mashimo, Richard Keeler, J. Steuerer, J. Pálinkás, J. M. Roney, Michael Kobel, Daniel Lellouch, O. C. Cooke, J. C. Hill, C. R. Jones, H. O. Ogren, K. Sachs, R. Kowalewski, Misao Sasaki, D. L. Rees, Shlomo Dado, Takehiko Mori, M. Schumacher, Mathieu Doucet, B. Wilkens, U. Müller, Joleen Pater, O. Schaile, E. Lefebvre, Peter Sherwood, Alexander Wagner, J. Ludwig, Christoph Geich-Gimbel, A. J. Martin, Julie Kirk, J. Letts, V. Zacek, K. Runge, P. Bock, Guenter Duckeck, W. Gorn, R. Giacomelli, D. Lanske, E. do Couto e Silva, Norbert Wermes, Sherry Towers, J. E. Conboy, F. Scharf, R. D. Heuer, Marco Cuffiani, F. Odorici, A. Rooke, J. G. Layter, T. Kawamoto, F. G. Oakham, J. von Krogh, Fabrizio Fabbri, K. Stephens, R. Howard, W. R. Gibson, J. S. White, Giora Mikenberg, K. Ametewee, German Martinez, D. J. Miller, S. Orito, M. Rosvick, B. T. Bouwens, R. J. Hawkings, B. Schmitt, E. L. Barberio, Sven Menke, A. Fürtjes, C. K. Hargrove, C. Charlesworth, Matthew Evans, Gideon Alexander, A. M. Rossi, R. Van Kooten, Paolo Capiluppi, L. A. del Pozo, Gunter Wolf, F. X. Gentit, V. Gibson, Lorne Levinson, S. B. Anderson, C. Sbarra, J. E. Pilcher, P. Szymanski, John Allison, N. K. Watson, T. R. Junk, T. Tsukamoto, A. Skillman, H. M. Fischer, G. Yekutieli, P. S. Wells, M. Fierro, D. R. Ward, H. Lafoux, T. Kress, J. E.G. Edwards, Terry Richard Wyatt, A. A. Carter, Ron Folman, Roger Jones, J. E. Bloomer, S. R. Lautenschlager, H. A. Neal, A. I. McNab, J. Goldberg, Stan Bentvelsen, F. Wäckerle, D. Chrisman, R. G. Kellogg, B. J. King, B. Nellen, T. Hilse, Volker Blobel, P. Utzat, O. Runolfsson, M. Steiert, D. M. Gingrich, H. G. Evans, W. Mohr, S. A. Robins, M. J. Goodrick, A. Posthaus, I. Cohen, Csaba Hajdu, C. Beeston, A. S. Turcot, Claudio Grandi, W. Matthews, P. E.L. Clarke, M. K. Jones, P. Berlich, Stefano Marcellini, K. Nagai, J. P. Martin, M. A. Thomson, D. R. Rust, Stephen Lloyd, M. Sproston, A. M. Lee, M. Kolrep, Robert M Brown, M. Tecchio, E. von Törne, M. Starks, A. Joly, S. De Jong, N. I. Geddes, Michael Hildreth, Ehud Duchovni, M. Jimack, N. L. Rodning, B. Poli, H. Przysiezniak, A. Michelini, A. N. Bell, Satoshi Tanaka, T. Kobayashi, M. F. Turner-Watson, R. Lahmann, M. Morii, D. C. Imrie, Peter R Hobson, P. Routenburg, G. P. Siroli, Sachio Komamiya, Theodoros Geralis, E. Ros, and T. P. Kokott
Subjects: Quark, Quantum chromodynamics, Physics, Nuclear and High Energy Physics, Particle physics, Astrophysics::High Energy Astrophysical Phenomena, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Charged particle, Gluon, Nuclear physics, High Energy Physics::Experiment, Multiplicity (chemistry), Nuclear Experiment, Parton shower, Particle Physics - Experiment
Abstract: Gluon jets with about 39 GeV energy are identified in hadronic Z 0 decays by tagging two jets in the same hemisphere of an event as quark jets. Identifying the gluon jet to be all the particles observed in the hemisphere opposite to that containing the two tagged jets yields an inclusive gluon jet definition corresponding to that used in analytic calculations, allowing the first direct test of those calculations. In particular, this jet definition yields results which are only weakly dependent on a jet finding algorithm. We find r ch. =1.552±0.0041 ( stat ) ±0.061 ( syst. ) for the ratio of the mean charged particle multiplicity in gluon jets to that in light quark uds jets, where the uds jets are identified using an inclusive jet definition similar to that used for the gluon jets. Our result is in general agreement with the prediction of a recent analytic calculation which incorporates energy conservation into the parton shower branching processes, but is considerably smaller than analytic predictions which do not incorporate energy conservation.
Published: 1996

23. Measurement of the branching fraction of the radiative decay τ → μνγ

Author: Frank Fiedler, S. M. Gascon-Shotkin, R. W. Springer, O. C. Cooke, R. Bartoldus, T. J. Smith, K. Stephens, V. Gibson, Silvia Arcelli, T. R. Junk, U. Ruppel, M. R. Ingram, D. R. Ward, H. Lafoux, T. Kress, G. G. Hanson, Achim Stahl, Matthias Schröder, C. Hartmann, D. E. Plane, Stephen Hillier, G. M. Dallavalle, A. I. McNab, D. Axen, A. Jawahery, R. Van Kooten, Otmar Biebel, Matthew Evans, H. O. Ogren, A. M. Rossi, G. Giacomelli, M. Thiergen, N. K. Watson, S. Yamashita, J. Goldberg, K. Sachs, Shlomo Dado, Christoph Geich-Gimbel, M. Schumacher, E. Lefebvre, P. Igo-Kemenes, P. Schenk, K. Ishii, H. Jeremie, B. Nellen, T. Tsukamoto, E. Tsur, M. Verzocchi, K. W. Bell, J. Pálinkás, E. A. Mckigney, S. R. Lautenschlager, H. A. Neal, W. P. Lai, Peter Sherwood, Alexander Wagner, S. L. Chu, John Allison, W. R. Gibson, M. S. Dixit, R. E. Hughes-Jones, J. Ludwig, J. C. Hill, Frans Meijers, Misao Sasaki, P. Poffenberger, J. Letts, K. Runge, P. Bock, F. Odorici, Norbert Wermes, H. G. Evans, W. J. McDonald, M. J. Goodrick, B. C. Shen, I. Cohen, J. Lauber, P. S. Wells, Sherry Towers, T. Kawamoto, F. Wäckerle, J. von Krogh, Gregor Herten, O. Schaile, E. do Couto e Silva, J. M. Roney, N. I. Geddes, Siegfried Bethke, A. K. Honma, B. Nijjhar, W. G. Scott, P. Schütz, D. M. Gingrich, B. T. Bouwens, Michael Hildreth, S. Orito, M. Rosvick, Dave Charlton, P. E.L. Clarke, M. K. Jones, P. Pfeifenschneider, Terry Richard Wyatt, T. Hilse, Giora Mikenberg, Gunter Wolf, F. X. Gentit, I. Nakamura, B. Wilkens, R. M. Brown, F. Strumia, S. D. Talbot, N. L. Rodning, M. Hapke, Lorne Levinson, J. P. Martin, B. Poli, A. Gaidot, J. E. Bloomer, P. Berlich, D. E. Hutchcroft, Sven Menke, R. Kowalewski, J. E. Conboy, James Pinfold, S. De Jong, S. Braibant, A. Fürtjes, H. M. Fischer, M. J. Oreglia, R. J. Hawkings, A. Skillman, J. Patt, D. G. Fong, C. Lewis, A. D. Schaile, Gabriella Pasztor, P. G. Estabrooks, R. K. Keeler, D. Glenzinski, Dezso Horvath, M. J. Losty, R. G. Kellogg, M. Steiert, Jean-Arcady Meyer, J. E. Pilcher, O. Runolfsson, U. Müller, U. Jost, H. Mes, R. Bürgin, J. R. Carter, G. N. Patrick, J. Gascon, P. M. Watkins, G. A. Snow, C. P. Ward, Csaba Hajdu, A. J. Martin, H. Przysiezniak, R. Mir, I. P. Duerdoth, P. Gagnon, S. A. Robins, L. A. del Pozo, Kiyotomo Kawagoe, A. N. Bell, P. Fath, Stefano Marcellini, Reda Tafirout, Klaus Kurt Desch, W. Mohr, S. Söldner-Rembold, T. Behnke, M. Boutemeur, F. S. Merritt, C. Beeston, A. Sittler, S. W. O'Neale, Stefan Kluth, K. J. Anderson, Shlomit Tarem, T. J. McMahon, Robert McPherson, Paolo Giacomelli, Claudio Grandi, A. Posthaus, D. M. Strom, M. Hansroul, K. Ametewee, A. Rooke, J. G. Layter, H. M. Bosch, F. G. Oakham, Ekg Sarkisyan, C. Burgard, R. K. Carnegie, M. Gruwé, B. Schmitt, C. Y. Chang, P. Taras, E. L. Barberio, Mathieu Doucet, R. Rylko, C. K. Hargrove, J. Bechtluft, P. W. Jeffreys, Michael Kobel, W. Matthews, R. J. Homer, Tara Shears, M. Bobinski, J. A. Wilson, C. Charlesworth, C. M. Hawkes, J. A. McKenna, Gideon Alexander, P. Weber, A. Joly, Daniel Lellouch, R. D. Heuer, Paolo Capiluppi, Gideon Bella, P. A. Hart, Takehiko Mori, Fabrizio Fabbri, Richard Nisius, C. H. Shepherd-Themistocleous, Marco Cuffiani, S. B. Anderson, P. Szymanski, A. Malik, H. J. Burckhart, M. J. Pearce, Jacqueline Batley, M. A. Thomson, D. Rigby, R. J. Hemingway, V. Zacek, K. Nagai, R. Lahmann, D. Lazic, D. C. Imrie, Julie Kirk, J. W. Gary, J. J. Ward, P. Vikas, D. Lanske, C. Sbarra, M. Starks, D. S. Koetke, D. Chrisman, D. R. Rust, B. Stockhausen, Paul Kyberd, E. K. U. Gross, F. K. Loebinger, G. P. Siroli, Volker Blobel, J. Steuerer, G. Yekutieli, Joleen Pater, Stefan Schmitt, Marcello Mannelli, G. Azuelos, G. W. Wilson, Stan Bentvelsen, R. Giacomelli, M. Hauschild, T. Omori, M. Sproston, R. Howard, S. A. Wotton, J. S. White, A. A. Carter, C. Markus, Ron Folman, Roger Jones, Stephen Lloyd, M. Fierro, J. E.G. Edwards, G. T. Jones, E. H. Vokurka, B. J. King, P. Utzat, B. W. Kennedy, P. Jovanovic, A. M. Lee, M. F. Turner-Watson, M. Morii, M. Tecchio, E. von Törne, Ehud Duchovni, M. Jimack, A. Michelini, C. R. Jones, Satoshi Tanaka, T. Kobayashi, Hans-Christian Schultz-Coulon, Austin Ball, Peter R Hobson, P. Scharff-Hansen, Randall Sobie, Michael Schulz, G. D. Lafferty, Peter Krieger, P. Mättig, Shoji Asai, P. Routenburg, Manuella Vincter, Alessandro Montanari, Sachio Komamiya, Guenter Duckeck, Theodoros Geralis, E. Ros, A. T. Watson, C. Dallapiccola, A. S. Turcot, I. J. Bloodworth, A. M. Smith, T. P. Kokott, N. Altekamp, H. Voss, G. Vasseur, R. J. Barlow, M. Kolrep, D. J. Miller, Andris Skuja, Yoram Rozen, S. Petzold, G. D. Long, Tetsuro Mashimo, M. Foucher, W. Gorn, D. Karlen, D. L. Rees, F. Scharf, and German Martinez
Subjects: Physics, Nuclear and High Energy Physics, Photon, Branching fraction, Electron–positron annihilation, Radiative transfer, Radiative decay, Rest frame, Atomic physics, Standard Model
Abstract: The branching ratio of the radiative τ decay τ − → μ − ν μ ν τ γ has been measured using data collected with the OPAL detector at LEP. The result is B(τ − → μ − ν μ ν τ γ) = (3.0 ± 0.4 ± 0.5) × 10 −3 for photon energies above 20 MeV measured in the τ rest frame. The result is in good agreement with the Standard Model expectation.
Published: 1996

24. Test of the four-fermion contact interaction in e+e− collisions at 130–140 GeV

Author: S. R. Lautenschlager, H. A. Neal, T. Hilse, O. Runolfsson, D. J. Miller, Claudio Grandi, T. R. Wyatt, R. J. Barlow, M. Fierro, J. E.G. Edwards, H. Mes, Ekg Sarkisyan, R. Bartoldus, P. W. Jeffreys, H. O. Ogren, Christoph Geich-Gimbel, Gideon Bella, Daniel Lellouch, C. H. Shepherd-Themistocleous, H. J. Burckhart, M. Hapke, S. M. Gascon-Shotkin, J. J. Ward, P. Vikas, D. Lanske, S. Braibant, Andris Skuja, S. Petzold, G. D. Long, Tetsuro Mashimo, Jacqueline Batley, P. G. Estabrooks, A. S. Turcot, R. K. Keeler, Takehiko Mori, I. P. Duerdoth, A. D. Schaile, T. Omori, M. J. Oreglia, Gabriella Pasztor, P. Fath, F. X. Gentit, V. Zacek, N. K. Watson, W. Gorn, Matthew Evans, A. M. Rossi, J. E. Conboy, A. Fürtjes, R. W. Springer, C. R. Jones, T. Tsukamoto, P. M. Watkins, G. A. Snow, C. P. Ward, S. Söldner-Rembold, H. M. Fischer, P. Poffenberger, P. Scharff-Hansen, G. N. Patrick, I. J. Bloodworth, Otmar Biebel, M. F. Turner-Watson, M. Morii, Peter R Hobson, J. Palinkas, A. M. Smith, P. Schütz, S. A. Robins, Yoram Rozen, Dave Charlton, Georges Azuelos, K. Sachs, P. Routenburg, Sachio Komamiya, M. Schumacher, E. Tsur, C. M. Hawkes, E. Lefebvre, M. Foucher, Shlomo Dado, S. L. Chu, W. Mohr, M. Boutemeur, F. S. Merritt, G. Vasseur, A. Posthaus, J. Letts, M. Verzocchi, James Pinfold, J. R. Carter, R. Bürgin, Silvia Arcelli, K. W. Bell, F. Odorici, Norbert Wermes, Sherry Towers, Theodoros Geralis, E. Ros, A. T. Watson, S. Yamashita, J. Lauber, T. Kawamoto, P. Igo-Kemenes, S. B. Anderson, P. Szymanski, G. Giacomelli, J. Bechtluft, J. A. McKenna, D. G. Fong, C. Lewis, Stefan Kluth, J. Gascon, Giora Mikenberg, Shlomit Tarem, D. Karlen, U. Jost, R. Mir, J. C. Hill, Misao Sasaki, C. Y. Chang, S. Orito, M. Rosvick, W. J. McDonald, K. Ishii, H. Jeremie, R. E. Hughes-Jones, N. I. Geddes, Michael Hildreth, F. Strumia, S. D. Talbot, T. P. Kokott, A. Luig, E. A. Mckigney, N. L. Rodning, P. Taras, A. Malik, J. W. Gary, W. P. Lai, D. S. Koetke, B. Poli, Marcello Mannelli, Michael Kobel, V. Gibson, O. Schaile, Stan Bentvelsen, B. C. Shen, Siegfried Bethke, A. K. Honma, W. G. Scott, I. Nakamura, Stefan Schmitt, D. L. Rees, A. I. McNab, F. Scharf, J. Goldberg, T. J. Smith, J. M. Roney, F. G. Oakham, B. Stockhausen, Paul Kyberd, F. K. Loebinger, E. do Couto e Silva, B. Schmitt, G. D. Lafferty, J. Steuerer, T. Behnke, German Martinez, Eilam Gross, Julie Kirk, E. L. Barberio, B. Nellen, P. Mättig, D. E. Hutchcroft, Joleen Pater, Sven Menke, D. Glenzinski, Shoji Asai, P. Gagnon, J. Allison, Reda Tafirout, Klaus Kurt Desch, P. A. Hart, M. Gruwé, R. Giacomelli, W. Matthews, C. Dallapiccola, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, A. Sittler, H. G. Evans, B. Nijjhar, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, H. M. Bosch, M. J. Pearce, M. A. Thomson, Richard Nisius, N. Altekamp, A. Gaidot, M. J. Goodrick, S. W. O'Neale, I. Cohen, M. Sproston, K. J. Anderson, Marco Cuffiani, A. Joly, C. Hartmann, Guenter Duckeck, D. E. Plane, D. Axen, A. Jawahery, Gunter Wolf, Matthias Schröder, R. Kowalewski, Peter Sherwood, M. Thiergen, D. Rigby, R. J. Hemingway, Stephen Hillier, G. M. Dallavalle, H. Lafoux, Alexander Wagner, J. Ludwig, K. Runge, K. Ametewee, P. Bock, B. W. Kennedy, P. Jovanovic, Gideon Alexander, Paolo Capiluppi, K. Stephens, Austin Ball, Peter Krieger, W. R. Gibson, R. G. Kellogg, Manuella Vincter, Alessandro Montanari, M. Steiert, Csaba Hajdu, Stefano Marcellini, B. T. Bouwens, U. Müller, A. J. Martin, D. Chrisman, Volker Blobel, Lorne Levinson, Stephen Lloyd, A. Skillman, Robert M Brown, T. R. Junk, C. K. Hargrove, Ehud Duchovni, M. Jimack, A. Michelini, D. R. Ward, Satoshi Tanaka, T. Kobayashi, T. Kress, Frank Fiedler, U. Ruppel, M. R. Ingram, Paolo Giacomelli, M. Hansroul, C. Burgard, R. J. Homer, Achim Stahl, T. J. McMahon, P. Pfeifenschneider, R. K. Carnegie, J. Patt, M. Bobinski, J. A. Wilson, G. G. Hanson, P. Schenk, D. Lazic, M. S. Dixit, C. Sbarra, Frans Meijers, G. Yekutieli, A. Rooke, J. G. Layter, C. Charlesworth, A. A. Carter, Ron Folman, Roger Jones, P. E.L. Clarke, M. K. Jones, J. P. Martin, S. De Jong, B. J. King, P. Utzat, H. Przysiezniak, A. N. Bell, O. C. Cooke, J. von Krogh, R. J. Hawkings, L. A. del Pozo, R. Lahmann, D. C. Imrie, G. P. Siroli, Kiyotomo Kawagoe, P. Weber, K. Nagai, P. S. Wells, D. R. Rust, J. E. Bloomer, D. M. Strom, R. Rylko, A. M. Lee, M. Tecchio, E. von Törne, R. Howard, J. S. White, R. Van Kooten, C.J. Beeston, T. G. Shears, F. Wäckerle, D. M. Gingrich, P. Berlich, Robert McPherson, Mathieu Doucet, R. D. Heuer, Fabrizio Fabbri, Gregor Herten, B. Wilkens, J. E. Pilcher, M. Starks, G. W. Wilson, M. Hauschild, S. A. Wotton, C. Markus, G. T. Jones, and E. H. Vokurka
Subjects: Nuclear physics, Physics, Nuclear and High Energy Physics, Electron–positron annihilation, Fermion, Particle Physics - Experiment, Standard Model
Abstract: The differential cross-sections for e + e − → e + e − , e + e − → μ + μ − and e + e − → τ + τ − , and the total cross-section for e + e − → qq at centre-of-mass energies of 130–140 GeV were studied using about 5 pb −1 of data collected with the OPAL detector at LEP in October and November 1995. The results are in agreement with the Standard Model predictions. Four-fermion contact interaction models were fitted to the data and lower limits were obtained on the energy scale Λ at the 95% confidence level.
Published: 1996

25. Prompt production in hadronic Z0 decays

Author: R. Van Kooten, Gideon Bella, C. H. Shepherd-Themistocleous, H. J. Burckhart, F. Wäckerle, C. Y. Chang, J. Lauber, P. Berlich, A. S. Turcot, M. Hapke, Ekg Sarkisyan, Jacqueline Batley, P. Taras, D. R. Rust, A. M. Lee, M. Tecchio, E. von Törne, Sachio Komamiya, D. E. Hutchcroft, R. Bartoldus, R. W. Springer, D. M. Strom, A. Rooke, G. Azuelos, T. Omori, I. J. Bloodworth, J. G. Layter, O. C. Cooke, S. Yamashita, P. Igo-Kemenes, Theodoros Geralis, E. Ros, A. T. Watson, Madjid Boutemeur, M. J. Oreglia, F. Strumia, S. D. Talbot, H. O. Ogren, Christoph Geich-Gimbel, P. W. Jeffreys, H. Fukui, C. Charlesworth, R. Rylko, Julie Kirk, H. Jeremie, K. Stephens, Gregor Herten, James Pinfold, J. E. Conboy, T. P. Kokott, R. E. Hughes-Jones, D. G. Fong, C. Lewis, H. Mes, I. P. Duerdoth, Gunter Wolf, F. X. Gentit, J. Gascon, Yoram Rozen, J. von Krogh, P. G. Estabrooks, R. K. Keeler, U. Jost, R. Mir, A. Luig, B. Wilkens, C. Hartmann, E. Tsur, D. E. Plane, M. Foucher, P. Fath, J. R. Carter, G. N. Patrick, G. G. Hanson, A. Fürtjes, R. J. Hawkings, J. P. Pansart, M. Verzocchi, K. W. Bell, E. do Couto e Silva, J. E. Pilcher, L. A. del Pozo, C. Sbarra, A. Malik, D. Karlen, C. Burgard, Stephen Hillier, S. B. Anderson, J. Pálinkás, P. Szymanski, J. W. Gary, Otmar Biebel, D. S. Koetke, P. S. Wells, P. Schenk, S. W. O'Neale, G. Yekutieli, Terry Richard Wyatt, Marcello Mannelli, Stefan Schmitt, E. Lefebvre, P. M. Watkins, K. J. Anderson, Sven Menke, G. M. Dallavalle, A. Sittler, F. S. Merritt, M. S. Dixit, Frans Meijers, J. E. Bloomer, Dave Charlton, A. A. Carter, Ron Folman, Roger Jones, T. J. Smith, F. G. Oakham, F. Odorici, J. C. Hill, Stan Bentvelsen, P. E.L. Clarke, M. K. Jones, H. M. Bosch, J. P. Martin, Misao Sasaki, W. J. McDonald, B. C. Shen, T. R. Junk, Siegfried Bethke, B. J. King, J. Bechtluft, J. A. McKenna, M. Kobe, M. Tscheulin, J. Ludwig, P. Utzat, O. Schaile, P. Mättig, Shoji Asai, R. Bürgin, M. F. Turner-Watson, Andris Skuja, S. Petzold, G. D. Long, Tetsuro Mashimo, M. Morii, S. De Jong, Silvia Arcelli, J. Letts, E. L. Barberio, Daniel Lellouch, N. Werrnes, B. Nijjhar, C. Dallapiccola, W. G. Scott, Sherry Towers, Peter R Hobson, P. Poffenberger, T. J. McMahon, J. J. Ward, P. Vikas, M. Starks, D. Lanske, Takehiko Mori, H. Przysiezniak, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, Stefan Kluth, Shlomit Tarem, T. Kawamoto, R. K. Carnegie, P. Routenburg, G. Giacomelli, D. Axen, P. Pfeifenschneider, W. Gorn, A. Jawahery, A. N. Bell, J. A. Wilson, D. R. Ward, H. Lafoux, R. J. Barlow, D. J. Miller, V. Zacek, P. Schütz, S. Orito, E. A. Mckigney, M. Rosvick, Reda Tafirout, Klaus Kurt Desch, A. I. McNab, Peter Sherwood, T. Kress, D. Lazic, G. W. Wilson, R. Howard, J. S. White, M. Hauschild, J. Goldberg, S. R. Lautenschlager, S. A. Wotton, Guenter Duckeck, W. P. Lai, P. Scharff-Hansen, Alexander Wagner, A. K. Honrna, A. Gaidot, K. Runge, P. Bock, C. Markus, Dezso Horvath, M. J. Losty, J. M. Roney, H. A. Neal, D. Rigby, R. J. Hemingway, Jean-Arcady Meyer, H. G. Evans, U. Ruppel, M. R. Ingram, M. J. Goodrick, G. T. Jones, E. H. Vokurka, T. Hilse, A. M. Smith, I. Cohen, B. W. Kennedy, P. Jovanovic, G. Vasseur, Austin Ball, Peter Krieger, Manuella Vincter, Alessandro Montanari, O. Runolfsson, S. Braibant, Gabriella Pasztor, C. Beeston, Claudio Grandi, G. A. Snow, C. P. Ward, P. Gagnon, S. Söldner-Rembold, A. Joly, M. Fierro, J. E.G. Edwards, C. R. Jones, Shlomo Dado, Paolo Giacomelli, Kiyotomo Kawagoe, M. Hansroul, P. Weber, Giora Mikenberg, R. Lahmann, D. C. Imrie, B. Stockhausen, Paul Kyberd, F. K. Loebinger, G. P. Siroli, R. J. Homer, S. L. Chu, J. Hoare, J. Steuerer, Joleen Pater, S. M. Gascon-Shotkin, Frank Fiedler, Achim Stahl, R. Giacomelli, B. Schmitt, N. Altekamp, Matthew Evans, A. M. Rossi, T. Behnke, U. Müller, A. J. Martin, T. Tsukamoto, Eilam Gross, John Allison, C. K. Hargrove, Matthias Schröder, M. Thiergen, M. Gruwé, C. M. Hawkes, Ehud Duchovni, D. M. Gingrich, M. Jimack, N. I. Geddes, B. Nellen, V. Gibson, Michael Hildreth, R. G. Kellogg, M. Steiert, A. Michelini, Tara Shears, Richard Nisius, Csaba Hajdu, N. L. Rodning, Marco Cuffiani, P. A. Hart, Stefano Marcellini, Satoshi Tanaka, T. Kobayashi, B. Poli, M. J. Pearce, H. M. Fischer, D. Chrisman, S. A. Robins, Volker Blobel, Stephen Lloyd, Robert M Brown, R. Kowalewski, K. Ametewee, Gideon Alexander, Paolo Capiluppi, W. R. Gibson, B. T. Bouwens, Lorne Levinson, Gilles Beaudoin, A. Skillman, Robert McPherson, Mathieu Doucet, R. D. Heuer, Fabrizio Fabbri, W. Matthews, M. A. Thomson, T. Wlodek, M. Sproston, D. L. Rees, F. Scharf, German Martinez, A. D. Schaile, N. K. Watson, W. Mohr, and A. Posthaus
Subjects: Physics, Nuclear physics, Nuclear and High Energy Physics, Particle physics, Meson, Branching fraction, Astrophysics::High Energy Astrophysical Phenomena, Electron–positron annihilation, Hadron, Energy spectrum, Tevatron, High Energy Physics::Experiment, Lepton
Abstract: Evidence is presented for the production of prompt J/psi mesons (not originating in b-hadron decays) in hadronic Z(0) decays. Using a sample of 3.6 million hadronic events, 24 prompt J/psi candidates are identified from their decays into e(+)e(-) and mu(+)mu(-)pairs. The background is estimated to be 10.2+/-2.0 events. The following branching ratio for prompt J/psi production is obtained: Br(Z(0)-->prompt J/psi+X)=(1.9+/-0.7+/-0.5+/-0.5). 10(-4), where the first error is statistical, the second systematic and the third error accounts for uncertainties in the prompt J/psi production mechanism.
Published: 1996

26. A first measurement of the Λ and ΛΛ () spin compositions in hadronic Z0 decays

Author: S. Yamashita, Dave Charlton, F. S. Merritt, W. J. McDonald, Stefan Kluth, Shlomit Tarem, B. C. Shen, Otmar Biebel, P. Igo-Kemenes, H. Jeremie, R. E. Hughes-Jones, Siegfried Bethke, R. Bürgin, O. Schaile, A. K. Honma, B. Nijjhar, D. E. Plane, W. G. Scott, Stephen Hillier, Robert McPherson, J. Bechtluft, Madjid Boutemeur, G. M. Dallavalle, J. A. McKenna, M. Starks, E. do Couto e Silva, H. O. Ogren, A. A. Carter, Christoph Geich-Gimbel, J. E. Conboy, U. Jost, R. Mir, A. Fürtjes, Stefan Schmitt, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, P. Poffenberger, Sven Menke, P. G. Estabrooks, R. K. Keeler, Mathieu Doucet, Gideon Bella, J. E. Bloomer, C. H. Shepherd-Themistocleous, H. J. Burckhart, R. D. Heuer, Fabrizio Fabbri, A. I. McNab, P. Schütz, P. M. Watkins, Jacqueline Batley, J. Goldberg, J. Letts, T. J. McMahon, P. Mättig, A. Gaidot, D. R. Rust, B. Nellen, E. Lefebvre, M. F. Turner-Watson, R. W. Springer, M. Morii, T. Omori, Gregor Herten, F. Odorici, A. Rooke, F. G. Oakham, Shoji Asai, Peter R Hobson, E. L. Barberio, Norbert Wermes, Sherry Towers, Reda Tafirout, Klaus Kurt Desch, R. K. Carnegie, B. Wilkens, J. G. Layter, H. G. Evans, C. Dallapiccola, C. Charlesworth, R. Howard, M. J. Goodrick, P. Routenburg, J. S. White, A. M. Lee, E. Tsur, J. A. Wilson, T. Kawamoto, I. Cohen, Sachio Komamiya, M. Verzocchi, M. Tecchio, E. von Törne, C. Y. Chang, Theodoros Geralis, E. Ros, A. T. Watson, K. W. Bell, J. P. Pansart, J. Pálinkás, Gunter Wolf, F. X. Gentit, I. J. Bloodworth, J. C. Hill, Misao Sasaki, J. E. Pilcher, P. E.L. Clarke, N. Altekamp, P. Taras, W. R. Gibson, Michael Kobel, M. K. Jones, E. A. Mckigney, R. J. Barlow, J. P. Martin, S. Orito, M. Tscheulin, H. Mes, A. S. Turcot, B. T. Bouwens, I. P. Duerdoth, D. J. Miller, A. Luig, M. Rosvick, S. De Jong, R. Bartoldus, W. P. Lai, P. Fath, Yoram Rozen, D. Lazic, C. R. Jones, M. Foucher, R. M. Brown, G. W. Wilson, M. Hauschild, Lorne Levinson, S. A. Wotton, O. C. Cooke, Julie Kirk, T. P. Kokott, D. Axen, Gilles Beaudoin, A. Jawahery, C. Markus, J. M. Roney, A. Skillman, H. Przysiezniak, D. M. Strom, R. Van Kooten, D. Rigby, R. J. Hemingway, A. N. Bell, D. Karlen, C. Burgard, G. T. Jones, B. W. Kennedy, E. H. Vokurka, Daniel Lellouch, H. Fukui, P. Jovanovic, G. G. Hanson, M. Hapke, Austin Ball, J. von Krogh, R. Rylko, M. Fierro, J. E.G. Edwards, Takehiko Mori, Ekg Sarkisyan, P. W. Jeffreys, Peter Krieger, Peter Sherwood, V. Zacek, F. Wäckerle, G. Giacomelli, D. M. Gingrich, S. W. O'Neale, Manuella Vincter, R. J. Hawkings, Alessandro Montanari, K. J. Anderson, L. A. del Pozo, P. Schenk, C. Sbarra, D. E. Hutchcroft, M. S. Dixit, Frans Meijers, P. Berlich, J. J. Ward, Alexander Wagner, J. Ludwig, P. Vikas, K. Runge, G. Yekutieli, P. Bock, D. Lanske, S. R. Lautenschlager, J. Lauber, M. J. Oreglia, P. S. Wells, H. A. Neal, Ron Folman, Roger Jones, T. Hilse, O. Runolfsson, B. J. King, P. Utzat, Terry Richard Wyatt, C. Beeston, Claudio Grandi, J. R. Carter, G. N. Patrick, F. Strumia, S. D. Talbot, G. Azuelos, P. Gagnon, A. Sittler, Hans-Christian Schultz-Coulon, H. M. Bosch, Randall Sobie, Michael Schulz, G. D. Lafferty, Guenter Duckeck, C. Hartmann, P. Szymanski, Stan Bentvelsen, M. Sproston, Andris Skuja, S. Petzold, G. D. Long, Tetsuro Mashimo, Achim Stahl, W. Gorn, B. Stockhausen, Paul Kyberd, F. K. Loebinger, B. Schmitt, J. Steuerer, Joleen Pater, R. Giacomelli, P. Scharff-Hansen, P. Pfeifenschneider, A. Joly, A. M. Smith, G. Vasseur, Paolo Giacomelli, John Allison, M. Hansroul, James Pinfold, R. G. Kellogg, D. G. Fong, C. Lewis, M. Steiert, J. Gascon, R. J. Homer, Csaba Hajdu, Stefano Marcellini, A. Malik, J. W. Gary, D. S. Koetke, Marcello Mannelli, J. Hoare, U. Ruppel, M. R. Ingram, T. J. Smith, K. Stephens, V. Gibson, T. Behnke, T. R. Junk, D. R. Ward, H. Lafoux, T. Kress, M. Gruwé, S. Braibant, C. M. Hawkes, Gabriella Pasztor, Frank Fiedler, G. A. Snow, C. P. Ward, S. Söldner-Rembold, R. Lahmann, D. C. Imrie, Shlomo Dado, G. P. Siroli, Giora Mikenberg, Richard Nisius, Kiyotomo Kawagoe, P. Weber, D. Chrisman, Marco Cuffiani, Volker Blobel, S. L. Chu, N. I. Geddes, Stephen Lloyd, Michael Hildreth, N. L. Rodning, B. Poli, Ehud Duchovni, M. Jimack, A. Michelini, H. M. Fischer, Satoshi Tanaka, T. Kobayashi, S. A. Robins, U. Müller, S. M. Gascon-Shotkin, A. J. Martin, Matthew Evans, A. M. Rossi, T. Tsukamoto, R. Kowalewski, C. K. Hargrove, Matthias Schröder, M. Thiergen, K. Ametewee, Gideon Alexander, Tara Shears, Paolo Capiluppi, P. A. Hart, M. J. Pearce, D. L. Rees, F. Scharf, German Martinez, A. D. Schaile, N. K. Watson, W. Mohr, A. Posthaus, W. Matthews, M. A. Thomson, E. K. U. Gross, and T. Wlodek
Subjects: Quantum chromodynamics, Physics, Nuclear and High Energy Physics, Spin states, Hadron, Hyperon, Nuclear physics, symbols.namesake, Pair production, Pauli exclusion principle, symbols, High Energy Physics::Experiment, Invariant mass, Spin (physics)
Abstract: The spin composition of Λ Λ , ΛΛ and Λ Λ pairs at low invariant mass values has been measured for the first time in multihadronic Z0 decays with the OPAL detector at LEP. No single spin state has been observed in the Λ Λ sample, verifying that the low mass enhancement in this sample, attributed to local baryon number compensation, is not a resonance state. The fraction of the spin 1 contribution to the Λ Λ pairs was found to be consistent with the value 0.75, as expected from a statistical spin mixture. This may be the net effect of many different QCD processes which contribute to the hyperon anti-hyperon pair production. The spin composition of the identical ΛΛ and Λ Λ pairs, well above threshold, is found to be similar to that of the Λ Λ sample. A ΛΛ emitter dimension is estimated from the data assuming the onset of the Pauli exclusion principle near threshold.
Published: 1996

27. Search for chargino and neutralino production using the OPAL detector at =130−136 GeV at LEP

Author: Tara Shears, W. J. McDonald, B. C. Shen, P. A. Hart, A. P. Wagner, Reda Tafirout, D. Chrisman, Volker Blobel, M. J. Pearce, Sachio Komamiya, Ekg Sarkisyan, Siegfried Bethke, B. Nijjhar, W. G. Scott, S. L. Chu, T. Behnke, J. Steuerer, M. Gruwé, C. M. Hawkes, Richard Nisius, P. Weber, Marco Cuffiani, Stephen Lloyd, G. G. Hanson, E. Ros, A. T. Watson, S. B. Anderson, P. Szymanski, Daniel Lellouch, T. J. Smith, K. Stephens, P. W. Jeffreys, E. Lefebvre, Andris Skuja, Koji Yoshimura, Takehiko Mori, S. Yamashita, W. R. Gibson, Madjid Boutemeur, F. Odorici, G. Giacomelli, Dezso Horvath, M. J. Losty, D. M. Strom, S. Petzold, G. D. Long, A. Joly, P. Poffenberger, P. Igo-Kemenes, Shlomo Dado, Matthias Schröder, T. P. Kokott, Stan Bentvelsen, Jean-Arcady Meyer, B. T. Bouwens, P. Schenk, M. Hauschild, A. Luig, Tetsuro Mashimo, H. Fukui, V. Zacek, F. S. Merritt, Ehud Duchovni, V. Gibson, P. G. Estabrooks, H. Jeremie, R. E. Hughes-Jones, R. K. Keeler, R. Rylko, R. M. Brown, Lorne Levinson, M. S. Dixit, M. Jimack, Frans Meijers, D. L. Rees, M. Hapke, M. Thiergen, H. Lafoux, D. E. Hutchcroft, Achim Stahl, F. Palmonari, Gilles Beaudoin, C. Sbarra, A. Skillman, F. Scharf, C. Markus, N. I. Geddes, German Martinez, J. J. Ward, W. Gorn, Michael Hildreth, P. Vikas, R. D. Heuer, P. M. Watkins, Giora Mikenberg, P. Schütz, E. do Couto e Silva, S. W. Gensler, Fabrizio Fabbri, S. Söldner-Rembol, A. S. Turcot, R. W. Springer, D. Lanske, A. D. Schaile, C. Hartmann, D. E. Plane, T. Kobayashi, J. Bechtluft, N. L. Rodning, B. Schmitt, Sven Menke, G. T. Jones, M. J. Oreglia, D. R. Ward, B. Stockhausen, Paul Kyberd, F. K. Loebinger, T. Kress, R. Lahmann, D. C. Imrie, M. Palazzo, J. A. McKenna, M. R. Ingram, E. H. Vokurka, James Pinfold, Stephen Hillier, Silvia Arcelli, G. M. Dallavalle, W. Matthews, B. Poli, S. Braibant, G. Yekutieli, D. R. Rust, Stefan Kluth, D. M. Gingrich, M. A. Thomson, E. Tsur, D. G. Fong, C. Lewis, Joleen Pater, C. Darling, Gabriella Pasztor, H. Mes, I. P. Duerdoth, Shlomit Tarem, J. Gascon, Paolo Giacomelli, M. Verzocchi, K. W. Bell, M. Hansroul, C. Y. Chang, E. K. U. Gross, R. Giacomelli, T. Hilse, R. Bartoldus, G. P. Siroli, J. King, P. Fath, O. Runolfsson, A. Gaidot, P. Mättig, J. Pálinkás, Shoji Asai, J. C. Hill, Gregor Herten, T. Wlodek, M. Sproston, S. M. Gascon-Shotkin, Christoph Geich-Gimbel, A. A. Carter, G. A. Snow, C. P. Ward, A. M. Lee, P. Taras, A. Rooke, Misao Sasaki, A. Malik, Carsten Daniel Burgard, J. G. Layter, Michael Kobel, M. Tecchio, A. H. Bain, I. J. Bloodworth, E. von Törne, J. W. Gary, Ron Folman, C. Beeston, E. A. Mckigney, W. P. Lai, R. Kowalewski, B. Wilkens, U. Müller, D. S. Koetke, C. Charlesworth, N. Tesch, J. R. Carter, G. N. Patrick, Otmar Biebel, Claudio Grandi, John Allison, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, Marcello Mannelli, Matthew Evans, Gunter Wolf, J. E. Pilcher, Julie Kirk, Stefania Xella, C. H. Shepherd-Themistocleous, A. M. Rossi, R. J. Homer, F. X. Gentit, A. J. Martin, R. Howard, Yoram Rozen, A. Fürtjes, M. F. Turner-Watson, N. K. Watson, K. Ametewee, M. Morii, Peter R Hobson, J. E. Conboy, J. S. White, Roger Jones, S. Wotton, J. P. Pansart, H. M. Fischer, J. M. Roney, P. Scharff-Hansen, P. E.L. Clarke, P. Utzat, M. K. Jones, Gideon Alexander, M. Foucher, A. Michelini, Paolo Capiluppi, R. G. Kellogg, J. P. Martin, R. Van Kooten, M. Tscheulin, P. Routenburg, A. I. McNab, S. De Jong, M. G. Rison, Guenter Duckeck, Frank Fiedler, J. Letts, G. W. Wilson, Junichi Kanzaki, S. A. Robins, D. Karlen, J. Goldberg, W. Mohr, O. Schaile, A. Posthaus, P. S. Wells, B. Nellen, M. Fierro, S. W. O'Neale, Norbert Wermes, Sherry Towers, T. Kawamoto, H. Przysiezniak, K. J. Anderson, T. J. McMahon, J. E.G. Edwards, A. M. Smith, Terry Richard Wyatt, C. K. Hargrove, M. Starks, J. E. Bloomer, A. N. Bell, F. Wäckerle, G. Vasseur, B. Lorazo, H. G. Evans, M. J. Goodrick, I. Cohen, S. Orito, J. Schwiening, M. Rosvick, R. K. Carnegie, P. Berlich, J. A. Wilson, O. C. Cooke, J. von Krogh, Csaba Hajdu, R. J. Hawkings, Stefano Marcellini, L. A. del Pozo, Gideon Bella, H. J. Burckhart, Jacqueline Batley, G. Azuelos, T. Omori, H. O. Ogren, D. Rigby, R. J. Hemingway, D. Axen, A. Jawahery, T. Geralis, B. W. Kennedy, P. Jovanovic, Peter Sherwood, Peter Krieger, Manuella Vincter, Alessandro Montanari, J. Ludwig, K. Runge, P. Bock, Dave Charlton, C. Dallapiccola, R. Bürgin, P. Gagnon, N. Altekamp, R. J. Barlow, D. J. Miller, A. K. Honma, U. Jost, R. Mir, A. Sittler, H. Takeda, F. G. Oakham, E. L. Barberio, H. M. Bosch, J. Lauber, and F. Strumia
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Electron–positron annihilation, High Energy Physics::Phenomenology, Detector, Scalar (mathematics), Lightest Supersymmetric Particle, Lower limit, Nuclear physics, Chargino, Neutralino, High Energy Physics::Experiment, Particle Physics - Experiment, Minimal Supersymmetric Standard Model
Abstract: A search for charginos and neutralinos, predicted by supersymmetric theories, has been performed using a data sample of 2.6 pb−1 at a centre-of-mass energy of S=130 GeV and 2.6 pb−1 at 136 GeV collected with the OPAL detector at LEP during November 1995. No candidate events were observed. The 95% C.L. lower limit on the lightest chargino mass in the Minimal Supersymmetric Standard Model is 65.4 GeV if the universal scalar mass m0 is greater than 1 TeV, and 58.7 GeV for the smallest m0 compatible with slepton and sneutrino mass limits obtained at centre-of-mass energies near the Z peak. These limits were obtained under the conditions that the lightest chargino is heavier than the lightest neutralino by more than 10 GeV and tan β is larger than 1.5. The results of a model independent search for charginos and neutralinos are also given.
Published: 1996

28. Topological search for the production of neutralinos and scalar particles

Author: C. Sbarra, G. Yekutieli, Ehud Duchovni, J. Lauber, Shlomo Dado, A. S. Turcot, Dave Charlton, A. A. Carter, Ron Folman, M. Jimack, Roger Jones, P. E.L. Clarke, M. K. Jones, Otmar Biebel, P. Utzat, Reda Tafirout, S. W. Gensler, T. Kobayashi, J. P. Martin, M. Kobe, M. Tscheulin, Matthias Schröder, Giora Mikenberg, M. Thiergen, F. Strumia, M. G. Rison, R. Bürgin, Andris Skuja, S. Petzold, G. D. Long, Frank Fiedler, P. S. Wells, Terry Richard Wyatt, J. E. Bloomer, H. Mes, I. P. Duerdoth, P. Fath, H. M. Fischer, A. Michelini, O. Schaile, M. Starks, Sachio Komamiya, Theodoros Geralis, E. Ros, R. Kowalewski, B. Stockhausen, Paul Kyberd, S. A. Robins, E. Lefebvre, F. Odorici, T. P. Kokott, K. Ametewee, F. K. Loebinger, S. De Jong, Tara Shears, Gideon Alexander, A. Luig, H. Przysiezniak, R. W. Springer, Tetsuro Mashimo, K. Stephens, Paolo Capiluppi, Gregor Herten, D. J. Miller, J. Steuerer, A. I. McNab, J. Goldberg, B. Nellen, R. Bartoldus, B. Wilkens, I. J. Bloodworth, J. Letts, P. A. Hart, R. Lahmann, D. C. Imrie, M. Palazzo, H. O. Ogren, S. Braibant, Gabriella Pasztor, Norbert Wermes, T. Behnke, A. N. Bell, S. Yamashita, J. P. Pansart, Joleen Pater, W. R. Gibson, Richard Keeler, M. J. Pearce, Mathieu Doucet, Georges Azuelos, Sherry Towers, V. Gibson, J. E. Pilcher, Christoph Geich-Gimbel, T. J. McMahon, P. Igo-Kemenes, E. Tsur, S. M. Gascon-Shotkin, G. P. Siroli, J. King, R. D. Heuer, Fabrizio Fabbri, T. Kawamoto, B. T. Bouwens, M. Verzocchi, D. Axen, A. Jawahery, G. A. Snow, C. P. Ward, G. W. Wilson, K. W. Bell, J. Pálinkás, H. Jeremie, M. Hauschild, H. G. Evans, J. Schwiening, R. K. Carnegie, M. J. Goodrick, I. Cohen, M. Gruwé, J. C. Hill, Misao Sasaki, S. Söldner-Rembold, Peter Sherwood, M. Fierro, J. E.G. Edwards, C. Markus, C. M. Hawkes, R. E. Hughes-Jones, D. Chrisman, Volker Blobel, R. Giacomelli, Yoram Rozen, D. R. Rust, J. A. Wilson, W. J. McDonald, B. C. Shen, Siegfried Bethke, A. K. Honma, W. Gorn, G. T. Jones, Alexander Wagner, Ekg Sarkisyan, Lorne Levinson, P. W. Jeffreys, Matthew Evans, E. H. Vokurka, S. Orito, M. Rosvick, M. F. Turner-Watson, Achim Stahl, J. Ludwig, A. Rooke, D. R. Ward, H. Lafoux, A. M. Rossi, T. Kress, B. Nijjhar, W. G. Scott, J. G. Layter, M. Morii, Peter R Hobson, K. Runge, P. Bock, A. J. Martin, Gilles Beaudoin, Richard Nisius, R. Howard, M. Foucher, A. Skillman, A. M. Lee, P. Routenburg, P. Weber, Marco Cuffiani, Stephen Lloyd, M. Tecchio, E. von Törne, Robert M Brown, Gideon Bella, C. H. Shepherd-Themistocleous, H. J. Burckhart, S. Asa, J. S. White, S. W. O'Neale, C. Charlesworth, M. R. Ingram, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, E. do Couto e Silva, P. Scharff-Hansen, P. Gagnon, Stefan Kluth, Shlomit Tarem, P. Bright-Thomas, K. J. Anderson, N. I. Geddes, Michael Hildreth, M. Hapke, D. E. Plane, S. L. Chu, Jacqueline Batley, B. Schmitt, O. C. Cooke, R. Van Kooten, Stephen Hillier, U. Müller, N. L. Rodning, B. Poli, C. K. Hargrove, D. Rigby, R. J. Hemingway, Stefania Xella, D. E. Hutchcroft, Junichi Kanzaki, G. M. Dallavalle, J. E. Conboy, J. J. Ward, P. Vikas, A. Fürtjes, P. Poffenberger, A. M. Smith, Sven Menke, A. Sittler, G. Vasseur, B. Lorazo, F. Wäckerle, D. Karlen, C. Burgard, T. Omori, D. M. Gingrich, Alan Watson, J. von Krogh, D. Lanske, B. W. Kennedy, P. Jovanovic, Silvia Arcelli, P. Schütz, M. J. Oreglia, P. Berlich, R. J. Hawkings, A. Gaidot, Gunter Wolf, F. X. Gentit, H. M. Bosch, G. G. Hanson, L. A. del Pozo, Austin Ball, Peter Krieger, James Pinfold, C. Y. Chang, D. G. Fong, C. Lewis, J. Gascon, D. M. Strom, C. Darling, P. Taras, T. J. Smith, Manuella Vincter, Alessandro Montanari, Paolo Giacomelli, M. Hansroul, A. Malik, G. Giacomelli, E. A. Mckigney, J. W. Gary, P. Mättig, D. S. Koetke, S. Wotton, Marcello Mannelli, R. J. Homer, J. R. Carter, G. N. Patrick, Julie Kirk, U. Jost, R. Mir, H. Fukui, P. Schenk, R. Rylko, Daniel Lellouch, T. Hilse, S. B. Anderson, C. Hartmann, Takehiko Mori, P. Szymanski, F. S. Merritt, O. Runolfsson, W. P. Lai, V. Zacek, H. Takeda, M. S. Dixit, Frans Meijers, F. G. Oakham, E. L. Barberio, C. Dallapiccola, C. Beeston, A. Joly, N. Altekamp, Stan Bentvelsen, R. J. Barlow, J. Bechtluft, J. A. McKenna, Claudio Grandi, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, Guenter Duckeck, J. M. Roney, John Allison, Madjid Boutemeur, R. G. Kellogg, Csaba Hajdu, Stefano Marcellini, P. G. Estabrooks, P. M. Watkins, Koji Yoshimura, D. L. Rees, F. Scharf, German Martinez, A. D. Schaile, N. K. Watson, W. Mohr, A. Posthaus, W. Matthews, M. A. Thomson, E. K. U. Gross, T. Wlodek, M. Sproston, and N. Tesch
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Missing energy, Electron–positron annihilation, High Energy Physics::Phenomenology, Scalar (mathematics), Supersymmetry, law.invention, Nuclear physics, law, Neutralino, High Energy Physics::Experiment, Neutrino, Collider, Particle Physics - Experiment, Minimal Supersymmetric Standard Model
Abstract: A search for scalar particles and neutralinos such as those predicted by supersymmetric models has been performed using a data sample of 4.4 million hadronic Z 0 decays recorded by the OPAL detector at the e + e − collider LEP. The production of such particles typically leads to event topologies consisting of an acoplanar pair of jets, or of a mono-jet, accompanied by sizeable missing energy owing to neutrinos and other undetectable neutral particles. Limits are obtained, at the 95% confidence level, on the masses and production rates of scalar particles produced in association with the Z 0 . Limits are also placed on neutralino production, for which an additional possible signature is also studied, events containing a single observed photon. Within the Minimal Supersymmetric Standard Model, the mass of the lightest neutralino is found to be larger than 12.5 GeV/ c 2 at 95% C.L., provided that tan β is larger than 1.5.
Published: 1996

29. A measurement of the tau mass and the first CPT test with tau leptons

Author: G. Abbiendi, K. Ackerstaff, C. Ainsley, 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, C. Bella, A. Bellerive, S. Bentvelsen, S. Bethke, O. Biebel, 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. Burckharth, J. Cammin, P. Capiluppi, R. K. Carnegie, A. A. Carter, J. R. Carter, C. Y. Chang, D. G. Charlton, C. Ciocca, P. E. L., E. Clay, I. Cohen, O. C. Cooke, J. Couchman, C. Couyoumtzelis, R. L. Cox, 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, M. Fanti, A. A. Faust, L. Feld, P. Ferrari, F. Fiedler, I. Fleck, M. Ford, 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, 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, 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. Keller, R. G. Kellogg, B. W. Kennedy, D. H. Kim, K. Klein, A. Klier, T. Kobayashi, M. Kobel, T. P. Kokott, 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, 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. Oh, A. Okpara, M. J. Oreglia, S. Orito, G. Pasztor, J. R. Pater, G. N. Patrick, J. Patt, P. Pfeifenschneider, J. E. Pilcher, J. Pinfold, D. E. Plane, B. Poli, J. Polok, O. Pooth, 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, S. Schmitt, 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, P. Vannerem, M. Verzocchi, H. Voss, J. Vossebeld, 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, D. Zer Zion, SPAGNOLO, Stefania Antonia, G., Abbiendi, K., Ackerstaff, C., Ainsley, 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, C., Bella, A., Bellerive, S., Bentvelsen, S., Bethke, O., Biebel, 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., Burckharth, J., Cammin, P., Capiluppi, R. K., Carnegie, A. A., Carter, J. R., Carter, C. Y., Chang, D. G., Charlton, C., Ciocca, P. E., L., E., Clay, I., Cohen, O. C., Cooke, J., Couchman, C., Couyoumtzeli, R. L., Cox, 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, M., Fanti, A. A., Faust, L., Feld, P., Ferrari, F., Fiedler, I., Fleck, M., Ford, 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, 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, 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., Keller, R. G., Kellogg, B. W., Kennedy, D. H., Kim, K., Klein, A., Klier, T., Kobayashi, M., Kobel, T. P., Kokott, 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, 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., Oh, A., Okpara, M. J., Oreglia, S., Orito, G., Pasztor, J. R., Pater, G. N., Patrick, J., Patt, P., Pfeifenschneider, J. E., Pilcher, J., Pinfold, D. E., Plane, B., Poli, J., Polok, O., Pooth, 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, 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, P., Vannerem, M., Verzocchi, H., Vo, J., Vossebeld, 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: Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, CPT symmetry, High Energy Physics::Phenomenology, FOS: Physical sciences, 01 natural sciences, Measure (mathematics), Confidence interval, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, Relative mass, High Energy Physics::Experiment, Nuclear Experiment, 010306 general physics, Particle Physics - Experiment, Lepton
Abstract: We measure the mass of the tau lepton to be 1775.1+-1.6(stat)+-1.0(syst.) MeV using tau pairs from Z0 decays. To test CPT invariance we compare the masses of the positively and negatively charged tau leptons. The relative mass difference is found to be smaller than 3.0 10^-3 at the 90% confidence level., Comment: 10 pages, 4 figures, Submitted to Phys. Letts. B
Published: 2000
Full Text: View/download PDF

30. Search for Higgs Bosons and Other Massive States decaying into two Photons in $e^{+}e^{-}$ Collisions at 189 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, 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, 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, J Couchman, 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, L Feld, 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, V Gibson, W.R Gibson, D.M Gingrich, D Glenzinski, J Goldberg, W Gorn, C Grandi, K Graham, E Gross, J Grunhaus, M Gruwé, C Hajdu, G.G Hanson, M Hansroul, M Hapke, K Harder, A Harel, C.K Hargrove, M Harin-Dirac, M Hauschild, C.M Hawkes, R Hawkings, R.J Hemingway, 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, 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, I Lawson, J.G Layter, 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, 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, P Mendez-Lorenzo, F.S Merritt, H Mes, 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, S Petzold, P Pfeifenschneider, J.E Pilcher, J Pinfold, D.E Plane, P Poffenberger, B Poli, J Polok, M Przybycień, A Quadt, 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, 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, Photon, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, FOS: Physical sciences, Fizikai tudományok, Fermion, Scalar boson, 01 natural sciences, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), Természettudományok, 0103 physical sciences, Higgs boson, High Energy Physics::Experiment, 010306 general physics, Particle Physics - Experiment, Boson
Abstract: A search is described for the generic process e+e- to X Y, where X is a neutral heavy scalar boson decaying into a pair of photons, and Y is a neutral heavy boson (scalar or vector) decaying into a fermion pair. The search is motivated mainly by the cases where either X, or both X and Y, are Higgs bosons. In particular, we investigate the case where X is the Standard Model Higgs boson and Y the Z0 boson. Other models with enhanced Higgs boson decay couplings to photon pairs are also considered. The present search combines the data set collected by the OPAL collaboration at 189 GeV collider energy, having an integrated luminosity of 182.6pb-1, with data samples collected at lower energies. The search results have been used to put 95% confidence level bounds, as functions of the mass of X, on the product of the cross-section and the relevant branching ratios, both in a model independent manner and for the particular models considered., Comment: 21 pages, LaTeX, including 5 eps figures, accepted by Phys. Lett. B
Published: 1999

31. 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

32. 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

33. 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

34. 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

35. 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

36. 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
Full Text: View/download PDF

37. 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

38. Search for charged Higgs bosons in e(+)e(-) collisions at root s = 130-172 GeV

Author: Silvia Arcelli, H. O. Ogren, Christoph Geich-Gimbel, J. Lauber, R. W. Springer, S. Baumann, E. A. Mckigney, Vakhtang Kartvelishvili, S. M. Gascon-Shotkin, K. Stoll, Andris Skuja, R. Davis, W. P. Lai, S. D. Talbot, S. Petzold, J. E. Conboy, A. Fürtjes, A. D. Schaile, W. R. Gibson, Gabriella Pasztor, P. Vannerem, D. Eatough, M. Schumacher, E. Lefebvre, E. Tsur, Tetsuro Mashimo, Lutz Feld, J. M. Roney, D. Lui, D. I. Futyan, F. Odorici, Matthew Evans, A. M. Rossi, G. A. Snow, C. P. Ward, M. Verzocchi, K. W. Bell, J. Pálinkás, C. Y. Chang, P. Taras, H. A. Neal, S. Söldner-Rembold, Michael Kobel, W. Gorn, S. Yamashita, J. C. Hill, P. Igo-Kemenes, K. Ishii, H. Jeremie, Richard Teuscher, O. Schaile, J. Grunhaus, Erez Etzion, S. Betts, M. Hapke, H. M. Fischer, Sven Menke, Dave Charlton, Stefan Kluth, M. A. Thomson, A. S. Turcot, E. K. U. Gross, Ehud Duchovni, Allen Mincer, F. Fiedler, Julie Kirk, P. G. Estabrooks, W. J. McDonald, B. C. Shen, Claire Shepherd-Themistocleous, R. K. Keeler, Shlomit Tarem, D. E. Hutchcroft, A. J. Martin, M. Boutemeur, F. S. Merritt, R. Bürgin, S. D. Bird, M. Jimack, M. Sproston, J. Letts, R. J. Hemingway, N. K. Watson, A. Michelini, Siegfried Bethke, B. W. Kennedy, L. Brigliadori, Sachio Komamiya, A. K. Honma, R. M. Brown, Lorne Levinson, M. J. Oreglia, P. Jovanovic, W. G. Scott, K. Sachs, Austin Ball, Theodoros Geralis, Daniel Lellouch, A. T. Watson, P. M. Watkins, I. Nakamura, D. Axen, A. Jawahery, Peter Krieger, Shlomo Dado, A. A. Faust, James Pinfold, R. Perez-Ochoa, Gideon Bella, M. Kolrep, H. J. Burckhart, S. A. Robins, T. Kobayashi, Takehiko Mori, D. G. Fong, H. Mes, I. P. Duerdoth, T. P. Kokott, J. Gascon, Alessandro Montanari, P. Mättig, S. Braibant, Jacqueline Batley, J. Bechtluft, T. Saeki, Peter Sherwood, K. Ackerstaff, U. Jost, R. Mir, R. Hawkings, C. K. Hargrove, V. Zacek, W. M. Sang, Alessandra Fanfani, Alexander Wagner, J. A. McKenna, A. Skillman, S. W. O'Neale, G. Azuelos, Tara Shears, Randall Sobie, G. D. Lafferty, Satoshi Mihara, T. Behnke, Giora Mikenberg, S. F. Ashby, K. J. Anderson, J. R. Carter, G. N. Patrick, J. W. Gary, N. I. Geddes, Michael Hildreth, D. Glenzinski, Dezso Horvath, D. S. Koetke, R. Kowalewski, M. J. Losty, J. Schieck, W. Mohr, Raimund Ströhmer, P. Hüntemeyer, Marcello Mannelli, C. R. Jones, J. Ludwig, P. A. Hart, K. Runge, P. Bock, Guenter Duckeck, N. L. Rodning, Jean-Arcady Meyer, F. G. Oakham, B. Schmitt, E. L. Barberio, A. Posthaus, B. Poli, P. Poffenberger, Otmar Biebel, P. Scharff-Hansen, I. J. Bloodworth, A. Macchiolo, A. Joly, C. Dallapiccola, J. Goldberg, Gideon Alexander, Paolo Capiluppi, C. M. Hawkes, S. B. Anderson, R. L. Coxe, P. Szymanski, B. Nellen, M. F. Turner-Watson, Peter R Hobson, N. Altekamp, H. Voss, A. M. Smith, P. Gagnon, R. J. Barlow, Beatrix Dienes, C. Sbarra, D. J. Miller, Yoram Rozen, F. Scharf, A. Hocker, Richard Nisius, K. Stephens, P. I. Kayal, D. Zer-Zion, Stan Bentvelsen, P. Routenburg, German Martinez, D. Chrisman, G. D. Long, B. List, M. Foucher, John Allison, Marco Cuffiani, Volker Blobel, H. G. Evans, M. Fierro, M. J. Goodrick, I. Cohen, A. Sittler, Peter Schleper, Junichi Kanzaki, D. Karlen, V. Gibson, Reda Tafirout, Klaus Kurt Desch, Zoltan Laszlo Trocsanyi, G. Yekutieli, Norbert Wermes, Sherry Towers, T. Kawamoto, Christoph Rembser, E. Torrence, Stefan Schmitt, S. Orito, R. G. Kellogg, Csaba Hajdu, P. E.L. Clarke, T. R. Junk, M. K. Jones, Stefano Marcellini, Stephen Lloyd, Shoji Asai, Ekg Sarkisyan, B. Stockhausen, Paul Kyberd, P. W. Jeffreys, J. P. Martin, F. K. Loebinger, I. Trigger, Matthias Schröder, J. Steuerer, Ivor Fleck, Joleen Pater, A. Klier, R. Giacomelli, D. R. Ward, A. Oh, T. Kress, S. De Jong, C. Hartmann, D. E. Plane, Stephen Hillier, U. Ruppel, G. M. Dallavalle, M. Thiergen, D. M. Gingrich, A. A. Carter, Ron Folman, Paolo Giacomelli, M. Hansroul, P. Vikas, D. Lanske, P. Utzat, S. R. Lautenschlager, A. Biguzzi, A. Rooke, C. Burgard, R. J. Homer, O. Runolfsson, J. G. Layter, Claudio Grandi, T. J. McMahon, O. C. Cooke, P. Pfeifenschneider, C. Couyoumtzelis, J. Patt, André Schöning, O. Sahr, R. K. Carnegie, M. Herndon, M. Bobinski, J. A. Wilson, R. Lahmann, D. C. Imrie, D. Lazic, Daniele Bonacorsi, G. P. Siroli, Christoph Schwick, J. von Krogh, G. G. Hanson, M. Gruwé, L. A. del Pozo, G. Giacomelli, I. Lawson, Kiyotomo Kawagoe, A. De Roeck, M. S. Dixit, Frans Meijers, K. R. Hossain, K. Nagai, D. R. Rust, A. M. Lee, E. von Törne, R. Van Kooten, F. Wäckerle, M. Fanti, Robert McPherson, Mathieu Doucet, R. D. Heuer, Fabrizio Fabbri, A. Macpherson, R. Howard, J. S. White, Ikuo Ueda, D. M. Strom, P. S. Wells, Terry Richard Wyatt, N. J. Oldershaw, S. Robertson, Gregor Herten, J. E. Pilcher, G. W. Wilson, M. Hauschild, C. Markopoulos, C. Markus, E. H. Vokurka, and R. Bartoldus
Subjects: Nuclear and High Energy Physics, Particle physics, Electron–positron annihilation, Microvertex Detector, FOS: Physical sciences, 01 natural sciences, 7. Clean energy, High-Energies, Lower limit, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, 010306 general physics, Boson, Physics, Luminosity (scattering theory), 010308 nuclear & particles physics, Branching fraction, High Energy Physics::Phenomenology, Monte-Carlo Program, LEP, Higgs boson, Couplings, High Energy Physics::Experiment, Decays, Cross-Sections, Particle Physics - Experiment
Abstract: A search is described to detect charged Higgs bosons via the process e^+e^- -> H^+H^-, using data collected by the OPAL detector at center-of-mass energies of 130-172 GeV with a total integrated luminosity of 25 pb^-1. The decay channels are assumed to be H^+ -> qq'(bar) and H^+ -> \tau^+ \nu_{\tau}. No evidence for charged Higgs boson production is observed. The lower limit for its mass is determined to be 52 GeV at 95% confidence level, independent of the H^+ -> \tau^+ \nu_{\tau} branching ratio., Comment: 19 pages, LaTeX, uses a4p.sty, 3 eps figures included, submitted to Phys. Lett. B
Published: 1998

39. First measurement of Z/gamma* production in Compton scattering of quasi-real photons

Author: K. Sachs, J. Goldberg, Shlomo Dado, Daniel Lellouch, Gideon Bella, J. Grunhaus, H. J. Burckhart, Giora Mikenberg, Jacqueline Batley, Stefan Schmitt, S. F. Ashby, B. Nellen, Shoji Asai, W. J. McDonald, B. C. Shen, S. D. Bird, Raimund Ströhmer, Otmar Biebel, Takehiko Mori, P. Mättig, H. A. Neal, Richard Teuscher, D. Axen, A. Jawahery, D. R. Rust, C. R. Jones, A. S. Turcot, F. Fiedler, A. D. Schaile, Gabriella Pasztor, H. G. Evans, G. Gaycken, I. J. Bloodworth, C. Hartmann, D. E. Plane, P. G. Bright-Thomas, I. Cohen, Peter Sherwood, Siegfried Bethke, P. I. Kayal, M. Schumacher, Stephen Hillier, Alexander Wagner, S. Yamashita, P. Vannerem, P. Igo-Kemenes, J. Ludwig, G. M. Dallavalle, K. Runge, M. A. Thomson, P. Poffenberger, P. Bock, Christoph Rembser, S. M. Gascon-Shotkin, F. Odorici, Yoram Rozen, E. K. U. Gross, K. Ishii, H. Jeremie, J. Letts, M. Sproston, P. Gagnon, Norbert Wermes, Sherry Towers, T. Kawamoto, J. Polok, Dave Charlton, G. A. Snow, C. P. Ward, D. Karlen, M. Fierro, R. Bartoldus, Beatrix Dienes, A. K. Honma, W. G. Scott, I. Nakamura, Erez Etzion, S. Orito, S. Söldner-Rembold, O. Schaile, A. Sittler, T. Seiler, R. Bürgin, Zoltan Laszlo Trocsanyi, M. Kolrep, Stefan Kluth, Ekg Sarkisyan, S. Betts, M. Hapke, S. Robertson, D. Liu, S. Baumann, Sachio Komamiya, Shlomit Tarem, A. T. Watson, W. R. Gibson, J. M. Roney, K. Harder, H. Mes, I. P. Duerdoth, Sven Menke, C. Y. Chang, J. Lauber, A. M. Rossi, E. A. Mckigney, S. Braibant, M. J. Oreglia, T. P. Kokott, S. D. Talbot, R. M. Brown, Lorne Levinson, Ehud Duchovni, Koichi Nagai, J. Schieck, W. Mohr, J. R. Carter, B. Surrow, T. Saeki, Christoph Geich-Gimbel, P. Taras, D. Glenzinski, S. A. Robins, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, P. Hüntemeyer, Stan Bentvelsen, H. O. Ogren, G. N. Patrick, Paul Kyberd, D. I. Futyan, F. K. Loebinger, L. Brigliadori, D. Lanske, K. Roscoe, S. R. Lautenschlager, R. Davis, R. Liebisch, K. Ackerstaff, S. W. O'Neale, K. J. Anderson, Klaus Kurt Desch, M. Jimack, P. G. Estabrooks, R. K. Keeler, O. Runolfsson, E. Torrence, E. Clay, Kiyotomo Kawagoe, N. K. Watson, Randall Sobie, G. D. Lafferty, F. Scharf, German Martinez, Claudia Ciocca, Claudio Grandi, J. S. White, J. Steuerer, Ivor Fleck, P. M. Watkins, Guenter Duckeck, Michael Hildreth, A. Michelini, Alain Bellerive, N. L. Rodning, S. Anderson, Joleen Pater, K. R. Hossain, Georges Azuelos, E. Tsur, A. Klier, D. C. Imrie, M. Verzocchi, K. W. Bell, J. Pálinkás, Satoshi Tanaka, T. Kobayashi, G. P. Siroli, J. C. Hill, Christoph Schwick, Vakhtang Kartvelishvili, R. L. Coxe, Satoshi Mihara, M. F. Turner-Watson, Peter R Hobson, J. E. Conboy, A. Fürtjes, A. Hocker, John Allison, D. Zer-Zion, D. Chrisman, G. D. Long, K. Stephens, Volker Blobel, C. Littlewood, R. G. Kellogg, V. Gibson, Stefano Marcellini, Stephen Lloyd, W. M. Sang, Paolo Giacomelli, M. Boutemeur, F. S. Merritt, M. Hansroul, I. Trigger, M. Fanti, C. Burgard, D. R. Ward, T. Kress, R. J. Homer, R. Kowalewski, S. Arcelli, T. R. Junk, C. Sbarra, Robert McPherson, F. R. Jacob, J. Bechtluft, Gideon Alexander, R. D. Heuer, A. W. Lloyd, P. S. Wells, Paolo Capiluppi, O. C. Cooke, J. A. McKenna, Fabrizio Fabbri, P. Pfeifenschneider, G. W. Wilson, M. Hauschild, C. Markopoulos, P. Scharff-Hansen, J. Patt, André Schöning, T. J. McMahon, C. Couyoumtzelis, J. Dubbert, R. K. Carnegie, M. Herndon, M. Bobinski, J. A. Wilson, J. Böhme, O. Sahr, D. Lazic, Terry Richard Wyatt, A. M. Lee, E. von Törne, Daniele Bonacorsi, A. M. Smith, J. von Krogh, F. Wäckerle, D. M. Gingrich, Achim Stahl, M. Gruwé, L. A. del Pozo, Gregor Herten, K. Stoll, A. J. Martin, G. Yekutieli, Andris Skuja, A. Macpherson, M. Przybycień, S. Petzold, W. Mader, C. K. Hargrove, J. E. Pilcher, Matthias Schröder, G. G. Hanson, A. A. Carter, Ron Folman, M. Thiergen, G. Giacomelli, I. Lawson, Tetsuro Mashimo, R. J. Hemingway, A. De Roeck, M. Kobel, R. Van Kooten, M. S. Dixit, Frans Meijers, Tara Shears, Giovanni Abbiendi, P. E.L. Clarke, B. W. Kennedy, J. P. Martin, P. Jovanovic, W. Gorn, S. De Jong, Austin Ball, Peter Krieger, R. Howard, H. Rick, Alessandro Montanari, A. Biguzzi, J. G. Layter, R. Mir, R. Hawkings, James Pinfold, D. M. Strom, R. Perez-Ochoa, R. Seuster, D. Eatough, T. Behnke, J. Gascon, V. Zacek, A. Macchiolo, J. W. Gary, F. G. Oakham, C. M. Hawkes, D. S. Koetke, Marcello Mannelli, B. Schmitt, E. L. Barberio, T. Kuhl, Richard Nisius, B. List, Marco Cuffiani, N. Altekamp, H. Voss, R. J. Barlow, D. J. Miller, Claire Shepherd-Themistocleous, and A. A. Faust
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Photon, 010308 nuclear & particles physics, Branching fraction, Astrophysics::High Energy Astrophysical Phenomena, Hadron, Monte Carlo method, Compton scattering, FOS: Physical sciences, Electron, 7. Clean energy, 01 natural sciences, 3. Good health, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Nuclear Experiment, Event (particle physics), Particle Physics - Experiment, Boson
Abstract: We report the first observation of Z/gamma* production in Compton scattering of quasi-real photons. This is a subprocess of the reaction e+e- to e+e-Z/gamma*, where one of the final state electrons is undetected. Approximately 55 pb-1 of data collected in the year 1997 at an e+e- centre-of-mass energy of 183 GeV with the OPAL detector at LEP have been analysed. The Z/gamma* from Compton scattering has been detected in the hadronic decay channel. Within well defined kinematic bounds, we measure the product of cross-section and Z/gamma* branching ratio to hadrons to be (0.9+-0.3+-0.1) pb for events with a hadronic mass larger than 60 GeV, dominated by (e)eZ production. In the hadronic mass region between 5 GeV and 60 GeV, dominated by (e)egamma* production, this product is found to be (4.1+-1.6+-0.6) pb. Our results agree with the predictions of two Monte Carlo event generators, grc4f and PYTHIA., Comment: 18 pages, LaTeX, 5 eps figures included, submitted to Physics Letters B
Published: 1998

40. Measurement of the Photon Structure Function F_2^gamma at Low x

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: Nuclear and High Energy Physics, Particle physics, Logarithm, FOS: Physical sciences, Generator, 01 natural sciences, Q2, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, 010306 general physics, Physics, Range (particle radiation), Luminosity (scattering theory), Parton Distributions, 010308 nuclear & particles physics, Scattering, Detector, Virtual Photons, LEP, Beam electron, Photon structure function, High Energy Physics::Experiment, Atomic physics, Particle Physics - Experiment
Abstract: Deep inelastic electron-photon scattering is studied using e+e- data collected by the OPAL detector at centre-of-mass energies sqrt{s_ee} ~ M_{Z^0}. The photon structure function F_2^gamma(x,Q^2) is explored in a Q^2 range of 1.1 to 6.6 GeV/c^2 at lower x values than ever before. To probe this kinematic region events are selected with a beam electron scattered into one of the OPAL luminosity calorimeters at scattering angles between 27 and 55 mrad. A measurement is presented of the photon structure function F_2^gamma(x,Q^2) at = 1.86 GeV^2 and 3.76 GeV^2 in five logarithmic x bins from 0.0025 to 0.2., Comment: 13 pages, LaTeX, uses a4p.sty, 3 eps figures included, submitted to Phys. Lett. B
Published: 1997

41. Spin alignment of leading $K^{*}(892)^{0}$ mesons in hadronic $Z^0$ decays

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. Davis, 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. Hutchroft, 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: Density matrix, Physics, Nuclear and High Energy Physics, Particle physics, Meson, 010308 nuclear & particles physics, Hadron, FOS: Physical sciences, 01 natural sciences, Helicity, High Energy Physics - Experiment, Standard Model, Momentum, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Particle Physics - Experiment, Spin-½, Bar (unit)
Abstract: Helicity density matrix elements for inclusive K*(892)^0 mesons from hadronic Z^0 decays have been measured over the full range of K^*0 momentum using data taken with the OPAL experiment at LEP. A preference for occupation of the helicity zero state is observed at all scaled momentum x_p values above 0.3, with the matrix element rho_00 rising to 0.66 +/- 0.11 for x_p > 0.7. The values of the real part of the off-diagonal element rho_1-1 are negative at large x_p, with a weighted average value of -0.09 +/- 0.03 for x_p > 0.3, in agreement with new theoretical predictions based on Standard Model parameters and coherent fragmentation of the qq(bar) system from the Z^0 decay. All other helicity density matrix elements measured are consistent with zero over the entire x_p range. The K^*0 fragmentation function has also been measured and the total rate determined to be 0.74 +/- 0.02 +/- 0.02 K*(892)^0 mesons per hadronic Z^0 decay., 19 pages, LaTeX, uses a4p.sty, pennames.sty, 4 eps figures included, submitted to Phys. Lett. B
Published: 1997

42. Search for unstable neutral and charged heavy leptons in $e^+ e^-$ collisions at $\sqrt{s}$ = 130 and 136 GeV

Author: S. R. Lautenschlager, H. A. Neal, T. Hilse, O. Runolfsson, C. Beeston, W. J. McDonald, Claudio Grandi, B. C. Shen, Ekg Sarkisyan, P. W. Jeffreys, A. I. McNab, J. Goldberg, B. Nellen, H. G. Evans, M. J. Goodrick, I. Cohen, Siegfried Bethke, A. K. Honma, B. Nijjhar, Gideon Bella, M. Boutemeur, F. S. Merritt, Stefan Kluth, Shlomit Tarem, P. Poffenberger, Sachio Komamiya, H. Mes, C. H. Shepherd-Themistocleous, H. J. Burckhart, Jacqueline Batley, T. J. Smith, K. Stephens, R. Van Kooten, W. G. Scott, I. Nakamura, U. Jost, R. Mir, Gunter Wolf, F. X. Gentit, P. Schütz, Theodoros Geralis, E. Ros, A. T. Watson, I. P. Duerdoth, P. Fath, T. J. McMahon, P. Scharff-Hansen, J. J. Ward, P. Vikas, J. Bechtluft, J. A. McKenna, D. Lanske, P. S. Wells, T. P. Kokott, A. Luig, R. K. Carnegie, D. Glenzinski, Dezso Horvath, G. G. Hanson, T. Behnke, T. Omori, M. J. Losty, Jean-Arcady Meyer, M. Bobinski, J. A. Wilson, Ehud Duchovni, Gregor Herten, F. G. Oakham, B. Schmitt, P. Gagnon, Terry Richard Wyatt, K. Sachs, Shlomo Dado, A. M. Smith, E. L. Barberio, M. Jimack, B. Stockhausen, Paul Kyberd, F. K. Loebinger, Reda Tafirout, Klaus Kurt Desch, G. Giacomelli, R. Bartoldus, M. Hapke, G. Vasseur, J. E. Bloomer, Andris Skuja, P. Schenk, A. Michelini, B. Wilkens, D. J. Miller, D. Lazic, A. Sittler, O. C. Cooke, S. Petzold, G. D. Long, Tetsuro Mashimo, C. R. Jones, D. Rigby, R. J. Hemingway, J. Steuerer, M. S. Dixit, Frans Meijers, H. O. Ogren, Christoph Geich-Gimbel, D. E. Hutchcroft, A. Gaidot, B. W. Kennedy, J. E. Pilcher, Satoshi Tanaka, M. Schumacher, E. Lefebvre, T. Kobayashi, P. E.L. Clarke, M. K. Jones, P. Jovanovic, W. Gorn, R. Lahmann, W. R. Gibson, M. Gruwé, H. M. Bosch, V. Gibson, Austin Ball, Giora Mikenberg, J. P. Martin, F. Odorici, Peter Krieger, D. C. Imrie, Joleen Pater, C. Y. Chang, M. Fierro, J. E.G. Edwards, J. von Krogh, C. M. Hawkes, James Pinfold, D. G. Fong, C. Lewis, J. Lauber, F. Wäckerle, U. Müller, B. T. Bouwens, S. De Jong, M. F. Turner-Watson, M. Morii, R. J. Hawkings, Manuella Vincter, P. Pfeifenschneider, J. Gascon, J. E. Conboy, A. Fürtjes, P. Taras, R. M. Brown, Peter R Hobson, G. P. Siroli, R. W. Springer, L. A. del Pozo, Alessandro Montanari, S. Braibant, Lorne Levinson, A. Malik, M. J. Oreglia, J. W. Gary, A. D. Schaile, D. S. Koetke, F. Strumia, S. D. Talbot, Marcello Mannelli, C. Sbarra, H. Przysiezniak, D. M. Gingrich, Dave Charlton, Michael Kobel, Richard Nisius, Gabriella Pasztor, G. W. Wilson, C. Dallapiccola, R. Howard, M. Hauschild, R. Giacomelli, A. Skillman, T. R. Junk, G. Yekutieli, R. Kowalewski, A. N. Bell, P. Routenburg, J. S. White, S. A. Wotton, Georges Azuelos, R. Bürgin, C. Hartmann, D. E. Plane, Marco Cuffiani, G. A. Snow, Stephen Hillier, E. Tsur, C. Markus, A. A. Carter, Ron Folman, Roger Jones, M. Verzocchi, K. W. Bell, A. J. Martin, N. Altekamp, R. J. Barlow, D. R. Ward, H. Lafoux, C. P. Ward, G. M. Dallavalle, A. Rooke, J. G. Layter, J. Pálinkás, B. J. King, Kiyotomo Kawagoe, S. B. Anderson, K. Ametewee, D. Axen, P. Szymanski, T. Kress, S. Söldner-Rembold, A. Jawahery, J. C. Hill, Misao Sasaki, P. Utzat, Julie Kirk, G. T. Jones, J. Patt, Gideon Alexander, E. H. Vokurka, J. R. Carter, D. M. Strom, C. Charlesworth, S. L. Chu, Peter Sherwood, Alexander Wagner, Paolo Capiluppi, G. N. Patrick, Otmar Biebel, P. Berlich, J. Ludwig, R. Rylko, P. Weber, K. Runge, P. Bock, D. Chrisman, Volker Blobel, Stephen Lloyd, S. W. O'Neale, K. J. Anderson, Frank Fiedler, A. Joly, M. Starks, U. Ruppel, M. R. Ingram, J. Letts, Paolo Giacomelli, M. Hansroul, Norbert Wermes, Sherry Towers, T. Kawamoto, C. Burgard, R. J. Homer, S. Orito, Stan Bentvelsen, M. Rosvick, P. G. Estabrooks, R. K. Keeler, Achim Stahl, N. I. Geddes, Michael Hildreth, N. L. Rodning, B. Poli, Robert McPherson, S. M. Gascon-Shotkin, Mathieu Doucet, P. M. Watkins, R. D. Heuer, Matthew Evans, C. K. Hargrove, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, Fabrizio Fabbri, A. M. Rossi, John Allison, T. Tsukamoto, K. Nagai, H. M. Fischer, Matthias Schröder, D. R. Rust, M. Thiergen, Silvia Arcelli, R. G. Kellogg, A. M. Lee, S. A. Robins, M. Steiert, M. Tecchio, E. von Törne, Csaba Hajdu, Stefano Marcellini, Tara Shears, Guenter Duckeck, E. A. Mckigney, P. A. Hart, M. J. Pearce, W. P. Lai, J. M. Roney, A. S. Turcot, D. L. Rees, F. Scharf, German Martinez, Daniel Lellouch, N. K. Watson, Takehiko Mori, V. Zacek, W. Mohr, S. Yamashita, A. Posthaus, W. Matthews, P. Igo-Kemenes, M. A. Thomson, K. Ishii, H. Jeremie, E. K. U. Gross, R. E. Hughes-Jones, M. Sproston, O. Schaile, E. do Couto e Silva, Sven Menke, Stefan Schmitt, P. Mättig, Shoji Asai, I. J. Bloodworth, Yoram Rozen, M. Foucher, and D. Karlen
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Astrophysics::High Energy Astrophysical Phenomena, Electron–positron annihilation, Dirac (video compression format), High Energy Physics::Phenomenology, Lower limit, Nuclear physics, Massless particle, MAJORANA, High Energy Physics::Experiment, Neutrino, Nuclear Experiment, Event (particle physics), Particle Physics - Experiment, Lepton
Abstract: Searches for unstable neutral and charged heavy leptons (L0, L±) have been performed using a data sample of 2.6 pb−1 at a centre-of-mass energy of s =130 GeV and 2.6 pb−1 at 136 GeV collected with the OPAL detector at LEP during November 1995. No candidate event was observed. If an unstable Dirac neutral heavy lepton L0 decays only into eW∗, μW∗ or τW∗, the lower limits on its mass at 95% C.L. are 62.5 GeV, 63.0 GeV and 57.4 GeV, respectively. The limits are modified for a Majorana L0 to 51.4 GeV, 52.2 GeV and 44.2 GeV, respectively. For charged heavy leptons, a lower mass limit of 64.5 GeV at 95% C.L. was obtained, if L± decays into a stable heavy neutrino ν l and W∗±, and m l± − mν l > 10 GeV. If L± decays through lepton flavour mixing into a massless neutrino νl and W∗±, the lower limit on m l± was determined to be 63.9 GeV at 95% C.L.
Published: 1996

43. Measurements with photonic events in e+e- collisions at centre-of-mass energies of 130-140 GeV

Author: G. Alexander, J. Allison, N. Altekamp, K. Ametewee, K.J. Anderson, S. Anderson, S. Arcelli, S. Asai, D. Axen, G. Azuelos, A.H. Ball, E. Barberio, R.J. Barlow, R. Bartoldus, J.R. Batley, G. Beaudoin, J. Bechtluft, C. Beeston, T. Behnke, A.N. Bell, K.W. Bell, G. Bella, S. Bentvelsen, P. Berlich, S. Bethke, O. Biebel, V. Blobel, I.J. Bloodworth, J.E. Bloomer, P. Bock, H.M. Bosch, M. Boutemeur, B.T. Bouwens, S. Braibant, R.M. Brown, H.J. Burckhart, C. Burgard, R. Bürgin, P. Capiluppi, R.K. Carnegie, A.A. Carter, J.R. Carter, C.Y. Chang, C. Charlesworth, D.G. Charlton, D. Chrisman, S.L. Chu, P.E.L. Clarke, I. Cohen, J.E. Conboy, O.C. Cooke, M. Cuffiani, S. Dado, C. Dallapiccola, G.M. Dallavalle, C. Darling, S. De Jong, L.A. del Pozo, M.S. Dixit, E. do Couto e Silva, M. Doucet, E. Duchovni, G. Duckeck, I.P. Duerdoth, J.E.G. Edwards, P.G. Estabrooks, H.G. Evans, M. Evans, F. Fabbri, P. Fath, F. Fiedler, M. Fierro, H.M. Fischer, R. Folman, D.G. Fong, M. Foucher, H. Fukui, A. Fürtjes, P. Gagnon, A. Gaidot, J.W. Gary, J. Gascon, S.M. Gascon-Shotkin, N.I. Geddes, C. Geich-Gimbel, S.W. Gensler, F.X. Gentit, T. Geralis, G. Giacomelli, P. Giacomelli, R. Giacomelli, V. Gibson, W.R. Gibson, D.M. Gingrich, J. Goldberg, M.J. Goodrick, W. Gorn, C. Grandi, E. Gross, 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, G. Herten, R.D. Heuer, M.D. Hildreth, J.C. Hill, S.J. Hillier, T. Hilse, P.R. Hobson, R.J. Homer, A.K. Honma, D. Horváth, R. Howard, R.E. Hughes-Jones, D.E. Hutchcroft, P. Igo-Kemenes, D.C. Imrie, M.R. Ingram, A. Jawahery, P.W. Jeffreys, H. Jeremie, M. Jimack, A. Joly, G. Jones, M. Jones, R.W.L. Jones, U. Jost, P. Jovanovic, J. Kanzaki, D. Karlen, T. Kawamoto, R.K. Keeler, R.G. Kellogg, B.W. Kennedy, J. King, J. Kirk, S. Kluth, T. Kobayashi, M. Kobel, D.S. Koetke, T.P. Kokott, S. Komamiya, R. Kowalewski, T. Kress, P. Krieger, J. von Krogh, P. Kyberd, G.D. Lafferty, H. Lafoux, R. Lahmann, W.P. Lai, D. Lanske, J. Lauber, J.G. Layter, A.M. Lee, E. Lefebvre, D. Lellouch, J. Letts, L. Levinson, C. Lewis, S.L. Lloyd, F.K. Loebinger, G.D. Long, B. Lorazo, M.J. Losty, J. Ludwig, A. Luig, A. Malik, M. Mannelli, S. Marcellini, C. Markus, A.J. Martin, J.P. Martin, G. Martinez, T. Mashimo, W. Matthews, P. Mättig, W.J. McDonald, J. McKenna, E.A. Mckigney, T.J. McMahon, A.I. McNab, F. Meijers, S. Menke, F.S. Merritt, H. Mes, J. Meyer, A. Michelini, G. Mikenberg, D.J. Miller, R. Mir, W. Mohr, A. Montanari, T. Mori, M. Morii, U. Müller, B. Nellen, B. Nijjhar, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, T. Omori, M.J. Oreglia, S. Orito, M. Palazzo, J. Pálinkás, J.P. Pansart, G. Pásztor, J.R. Pater, G.N. Patrick, M.J. Pearce, S. Petzold, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, B. Poli, A. Posthaus, H. Przysiezniak, D.L. Rees, D. Rigby, M.G. Rison, S.A. Robins, N. Rodning, J.M. Roney, A. Rooke, E. Ros, A.M. Rossi, M. Rosvick, P. Routenburg, Y. Rozen, K. Runge, O. Runolfsson, D.R. Rust, R. Rylko, E.K.G. Sarkisyan, M. Sasaki, C. Sbarra, A.D. Schaile, O. Schaile, F. Scharf, P. Scharff-Hansen, P. Schenk, B. Schmitt, M. Schröder, H.C. Schultz-Coulon, M. Schulz, P. Schütz, J. Schwiening, 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, T.J. Smith, G.A. Snow, R. Sobie, S. Söldner-Rembold, R.W. Springer, M. Sproston, A. Stahl, M. Starks, K. Stephens, J. Steuerer, B. Stockhausen, D. Strom, F. Strumia, P. Szymanski, R. Tafirout, H. Takeda, P. Taras, S. Tarem, M. Tecchio, N. Tesch, M. Thiergen, M.A. Thomson, E. von Törne, S. Towers, M. Tscheulin, E. Tsur, A.S. Turcot, M.F. Turner-Watson, P. Utzat, R. Van Kooten, G. Vasseur, M. Verzocchi, P. Vikas, M. Vincter, E.H. Vokurka, F. Wäckerle, A. Wagner, C.P. Ward, D.R. Ward, J.J. Ward, P.M. Watkins, A.T. Watson, N.K. Watson, P. Weber, P.S. Wells, N. Wermes, J.S. White, B. Wilkens, G.W. Wilson, J.A. Wilson, T. Wlodek, G. Wolf, S. Wotton, T.R. Wyatt, S. Xella, S. Yamashita, G. Yekutieli, K. Yoshimura, and V. Zacek
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Photon, Mass distribution, business.industry, Electron–positron annihilation, Resonance, law.invention, Standard Model, Nuclear physics, law, Excited state, High Energy Physics::Experiment, Photonics, business, Collider, Particle Physics - Experiment
Abstract: Cross-sections and angular distributions for the production of events with single and multiple photons are measured from data recorded with the OPAL detector at the recently upgraded LEP collider. The measured cross-sections are generally consistent with Standard Model expectations for the e + e − → ν v γ(γ) and e+e− → γγ(γ) processes. Six events with an acoplanar photon pair and large missing mass are found. The observed number of events is larger than expected from e + e − → ν ν γγ ; however, the missing mass distribution is compatible with the Z0 resonance. Deviations from QED are constrained by the data on e+e− → γγ(γ). Lower limits are set at 95% confidence level on the QED cut-off parameters Λ+ and Λ− of 152 GeV and 142 GeV, respectively, and also on the mass of an excited electron of 147 GeV.
Published: 1996

44. Measurement of cross-sections and asymmetries in e+e- collisions at 130-140 GeV centre-of-mass energy

Author: A. I. McNab, Sachio Komamiya, Theodoros Geralis, E. Ros, A. T. Watson, T. P. Kokott, A. Luig, H. Mes, I. P. Duerdoth, M. F. Turner-Watson, M. Morii, Peter R Hobson, Madjid Boutemeur, P. Routenburg, J. Lauber, D. Rigby, R. J. Hemingway, Otmar Biebel, Gideon Bella, J. Goldberg, F. G. Oakhamh, O. C. Cooke, P. Fath, C. H. Shepherd-Themistocleous, H. J. Burckhart, Tara Shears, Koji Yoshimura, B. W. Kennedy, P. Jovanovic, P. E.L. Clarke, M. K. Jones, Jacqueline Batley, J. P. Martin, P. A. Hart, Austin Ball, Peter Krieger, R. W. Springer, S. Yamashita, J. von Krogh, P. G. Estabrooks, R. K. Keeler, Gregor Herten, M. Tscheulin, Michael Hildreth, S. De Jong, J. Letts, Manuella Vincter, Alessandro Montanari, Norbert Wermes, Georges Azuelos, N. L. Rodning, M. J. Pearce, M. St arks, Sherry Towers, P. M. Watkins, T. Kawamoto, H. G. Evans, E. Tsur, R. J. Hawkings, U. Jost, R. Mir, D. L. Rees, F. Scharf, B. Poli, Paolo Giacomelli, M. Hansroul, H. Przysiezniak, German Martinez, T. Omori, F. Strumia, M. Verzocchi, I. Cohen, K. W. Bell, Hans-Christian Schultz-Coulon, L. A. del Pozo, B. Stockhausen, Paul Kyberd, F. K. Loebinger, T. Hilse, A. D. Schaile, P. Igo-Kemenes, B. Wilkens, J. P. Pansart, R. Van Kooten, S. Orito, M. Rosvick, P. Weber, J. Pálinkás, T. J. McMahon, A. N. Bell, J. Steuerer, Randall Sobie, O. Runolfsson, Michael Schulz, G. D. Lafferty, Frank Fiedler, E. Lefebvre, W. Matthews, J. C. Hill, Misao Sasaki, H. Takeda, H. Jeremie, J. Schwiening, Yoram Rozen, Gunter Wolf, F. X. Gentit, R. K. Carnegie, R. J. Homer, M. A. Thomson, F. Odorici, Silvia Arcelli, M. Hapke, W. J. McDonald, B. C. Shen, J. E. Pilcher, E. L. Barberio, S. M. Gascon-Shotkin, M. Foucher, Matthias Schröder, M. R. Ingram, R. E. Hughes-Jones, Joleen Pater, R. Howard, D. E. Hutchcroft, Siegfried Bethke, I. J. Blood worth, J. A. Wilson, T. Wlodek, C. Dallapiccola, M. Sproston, J. S. White, A. K. Honma, B. Nijjhar, W. G. Scott, A. Rooke, R. Giacomelli, M. Thiergen, C. Beeston, S. Wotton, S. L. Chu, M. J. Oreglia, J. G. Layter, Achim Stahl, Claudio Grandi, Junichi Kanzaki, N. Altekamp, D. Karlen, C. Burgard, N. Tesch, E. A. Mckigney, M. J. Goodrich, R. J. Barlow, Matthew Evans, C. Sbarra, Shlomo Dado, Ekg Sarkisyan, P. W. Jeffreys, W. P. Lai, A. M. Rossi, N. K. Watson, Guenter Duckeck, O. Schaile, E. do Couto e Silva, Dezso Horvath, M. J. Losty, F. Wäckerle, C. Charlesworth, Jean-Arcady Meyer, J. R. Carter, G. Yekutieli, B. Schmitt, H. M. Fischer, A. Michelini, J. M. Roney, G. N. Patrick, B. Nellen, N. I. Geddest, A. A. Carter, Ron Folman, Roger Jones, C. Darling, D. M. Gingrich, John Allison, P. S. Wells, Stefan Kluth, W. Mohr, Sven Menke, D. Axen, T. J. Smith, Shlomit Tarem, A. Posthaus, Stefania Xella, A. S. Turcot, U. Müller, R. Lahmann, A. Jawahery, D. C. Imrie, M. Palazzo, P. Utzat, Giora Mikenberg, Terry Richard Wyatt, K. Stephens, S. A. Robins, J. E. Bloomer, A. J. Martin, T. Behnke, M. G. Rison, G. W. Wilson, J. J. Ward, P. Mättig, Shoji Asai, Peter Sherwood, M. Hauschild, P. Vikas, Eilam Gross, D. Lanske, G. P. Siroli, S. Braibant, Gabriella Pasztor, J. King, P. Berlich, Alexander Wagner, R. G. Kellogg, C. Markus, V. Gibson, Dave Charlton, J. Ludwig, Csaba Hajdu, G. A. Snow, C. P. Ward, G. G. Hanson, M. Gruwé, G. T. Jones, D. J. Miller, C. M. Hawkes, K. Runge, P. Bock, S. Söldner-Rembold, C. K. Hargrove, Daniel Lellouch, E. H. Vokurka, Stefano Marcellini, D. M. Strom, Richard Nisius, P. Gagnon, D. R. Ward, H. Lafoux, T. Kress, S. B. Anderson, P. Szymanski, H. Fukui, R. Bürgin, R. Rylko, Marco Cuffiani, M. Fierro, J. E.G. Edwards, Takehiko Mori, A. Sittler, P. Schenk, G. Giacomelli, H. M. Bosch, Stan Bentvelsen, M. S. Dixit, Frans Meijers, V. Zacek, A. Joly, Mathieu Doucet, R. D. Heuer, Fabrizio Fabbri, D. R. Rust, A. M. Lee, M. Tecchio, E. von Törne, Reda Tafirout, James Pinfold, W. R. Gibson, D. Chrisman, Volker Blobel, D. G. Fong, C. Lewis, B. T. Bouwens, J. Gascon, Lorne Levinson, A. Malik, J. W. Gary, D. S. Koetke, Gilles Beaudoin, Marcello Mannelli, Andris Skuja, Stephen Lloyd, A. Skillman, S. Petzold, G. D. Long, Tetsuro Mashimo, Robert M Brown, C. Hartmann, D. E. Plane, Stephen Hillier, W. Gorn, G. M. Dallavalle, P. Scharff-Hansen, A. M. Smith, G. Vasseur, B. Lorazo, Ehud Duchovni, R. Bartoldus, H. O. Ogren, Christoph Geich-Gimbel, J. E. Conboy, A. Fürtjes, M. Jimack, F. S. Merritt, J. Bechtluft, J. A. McKenna, S. W. Gensler, T. Kobayashi, R. Kowalewski, K. Ametewee, Gideon Alexander, Paolo Capiluppi, S. W. O'Neale, K. J. Anderson, P. Poffenberger, P. Schütz, A. Gaidot, C. Y. Chang, P. Taras, Michael Kobel, and Julie Kirk
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Photon, Electron–positron annihilation, High Energy Physics::Phenomenology, Hadron, Resonance (particle physics), Standard Model, Nuclear physics, Radiative transfer, High Energy Physics::Experiment, Energy (signal processing), Particle Physics - Experiment, Lepton
Abstract: Production of events with multihadronic and leptonic final states has been measured in e + e − collisions at centre-of-mass energies significantly above the Z 0 mass, using the OPAL detector at LEP. A substantial production rate of radiative Z 0 γ events was observed, as expected, together with events with less energetic initial-state photons. The cross-sections and leptonic forward-backward asymmetries were measured and compared with Standard Model expectations. In a model-independent fit to the Z 0 lineshape, the hadronic cross-section and lepton asymmetries presented here provide constraints on the size of the γZ 0 -interference term which are complementary to those afforded by LEP data accumulated at the Z 0 resonance.
Published: 1996

45. Production of fermion-pair events in e(+)e(-) collisions at 161 GeV centre-of-mass energy

Author: J. Goldberg, B. Nellen, T. J. McMahon, W. J. McDonald, P. A. Hart, R. K. Carnegie, M. Herndon, M. Bobinski, J. A. Wilson, D. Lazic, D. R. Rust, H. Mes, Stefan Schmitt, B. Nijjhar, M. J. Pearce, I. P. Duerdoth, B. C. Shen, P. Fath, T. J. Smith, R. Lahmann, D. C. Imrie, H. G. Evans, M. J. Goodrick, I. Cohen, Siegfried Bethke, A. K. Honma, S. Braibant, M. Hapke, D. M. Strom, A. M. Lee, E. von Törne, A. D. Schaile, Gabriella Pasztor, K. Stephens, P. Mättig, Shoji Asai, Dave Charlton, P. Poffenberger, Gunter Wolf, K. Ackerstaff, W. G. Scott, I. Nakamura, I. J. Bloodworth, D. E. Hutchcroft, H. M. Fischer, P. Scharff-Hansen, Claire Shepherd-Themistocleous, Silvia Arcelli, R. Bürgin, S. Yamashita, S. B. Anderson, P. Szymanski, Ehud Duchovni, P. Igo-Kemenes, V. Gibson, R. Rylko, G. P. Siroli, G. A. Snow, M. J. Oreglia, C. P. Ward, R. Van Kooten, S. Robertson, Matthias Schröder, Stan Bentvelsen, Gregor Herten, D. J. Miller, G. Giacomelli, K. Ishii, H. Jeremie, R. E. Hughes-Jones, M. Thiergen, M. Jimack, Achim Stahl, Yoram Rozen, Gideon Bella, A. Michelini, T. R. Junk, P. Schütz, S. A. Robins, H. J. Burckhart, S. Söldner-Rembold, B. Wilkens, C.J. Beeston, C. Hartmann, Jacqueline Batley, I. Trigger, D. E. Plane, M. Foucher, M. Schumacher, T. Behnke, Satoshi Tanaka, T. Kobayashi, D. Glenzinski, Dezso Horvath, T. G. Shears, O. Schaile, E. do Couto e Silva, D. M. Gingrich, D. R. Ward, T. R. Wyatt, Eilam Gross, Hans-Christian Schultz-Coulon, Stephen Hillier, T. Kress, E. Lefebvre, M. J. Losty, J. E. Pilcher, Randall Sobie, Michael Schulz, Jean-Arcady Meyer, G. Azuelos, F. Wäckerle, P. Gagnon, A. M. Smith, T. Omori, E. A. Mckigney, U. Ruppel, M. R. Ingram, M. Gruwé, C. M. Hawkes, F. Odorici, G. M. Dallavalle, R. Howard, J. S. White, J. R. Carter, Kiyotomo Kawagoe, Sven Menke, G. W. Wilson, R. J. Barlow, Richard Nisius, G. N. Patrick, K. Sachs, Otmar Biebel, M. Hauschild, Stefan Kluth, Shlomit Tarem, S. A. Wotton, W. P. Lai, C. R. Jones, U. Müller, D. Karlen, Shlomo Dado, Marco Cuffiani, S. M. Gascon-Shotkin, C. Markus, P. Berlich, K. Ametewee, J. Allison, A. J. Martin, Guenter Duckeck, M. Fierro, J. E.G. Edwards, Ekg Sarkisyan, R. W. Springer, C. Y. Chang, Gideon Alexander, G. T. Jones, E. H. Vokurka, P. W. Jeffreys, Paolo Capiluppi, P. S. Wells, J. E. Bloomer, James Pinfold, J. M. Roney, A. S. Turcot, F. Fiedler, P. Pfeifenschneider, N. J. Oldershaw, A. Sittler, Matthew Evans, G. D. Lafferty, A. M. Rossi, D. Chrisman, P. Taras, Daniel Lellouch, E. Tsur, D. G. Fong, C. Lewis, Giora Mikenberg, T. Tsukamoto, C. Sbarra, Volker Blobel, P. Schenk, J. Patt, G. Yekutieli, A. A. Carter, Ron Folman, Roger Jones, M. Verzocchi, K. W. Bell, J. Pálinkás, Takehiko Mori, B. J. King, Michael Kobel, P. Utzat, W. R. Gibson, J. Gascon, O. C. Cooke, M. Kolrep, J. C. Hill, Stephen Lloyd, Robert M Brown, J. von Krogh, R. J. Hawkings, L. A. del Pozo, Misao Sasaki, J. Letts, V. Zacek, N. I. Geddes, Michael Hildreth, J. J. Ward, P. G. Estabrooks, R. K. Keeler, H. M. Bosch, P. Vikas, B. T. Bouwens, Norbert Wermes, Julie Kirk, C. K. Hargrove, D. Lanske, Robert McPherson, Sherry Towers, T. Kawamoto, Paolo Giacomelli, R. G. Kellogg, M. Steiert, N. L. Rodning, B. Poli, M. Hansroul, Csaba Hajdu, P. M. Watkins, S. R. Lautenschlager, H. A. Neal, Mathieu Doucet, R. D. Heuer, Stefano Marcellini, C. Burgard, S. Orito, Lorne Levinson, T. Hilse, R. J. Homer, Fabrizio Fabbri, O. Runolfsson, M. Rosvick, J. W. Gary, A. Joly, A. Skillman, D. S. Koetke, D. Axen, A. Jawahery, B. Stockhausen, Paul Kyberd, F. K. Loebinger, S. W. O'Neale, Claudio Grandi, J. Steuerer, Joleen Pater, Marcello Mannelli, R. Giacomelli, K. J. Anderson, Andris Skuja, Reda Tafirout, Klaus Kurt Desch, S. Petzold, G. D. Long, Peter Sherwood, Tetsuro Mashimo, Alexander Wagner, J. Ludwig, K. Runge, P. Bock, M. F. Turner-Watson, M. Morii, J. Lauber, Peter R Hobson, P. Routenburg, W. Gorn, Sachio Komamiya, Theodoros Geralis, E. Ros, A. T. Watson, T. P. Kokott, F. Strumia, S. D. Talbot, J. Grunhaus, R. Bartoldus, H. O. Ogren, D. Rigby, R. J. Hemingway, Christoph Geich-Gimbel, J. E. Conboy, B. W. Kennedy, P. Jovanovic, Austin Ball, Peter Krieger, A. Fürtjes, Manuella Vincter, Alessandro Montanari, U. Jost, R. Mir, M. Boutemeur, F. S. Merritt, F. G. Oakham, B. Schmitt, E. L. Barberio, C. Dallapiccola, N. Altekamp, J. Bechtluft, J. A. McKenna, W. Matthews, M. A. Thomson, M. Sproston, D. L. Rees, F. Scharf, German Martinez, N. K. Watson, W. Mohr, A. Posthaus, P. E.L. Clarke, M. K. Jones, J. P. Martin, S. De Jong, H. Przysiezniak, A. N. Bell, G. G. Hanson, M. S. Dixit, Frans Meijers, A. Rooke, J. G. Layter, A. I. McNab, and K. Nagai
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Annihilation, Branching fraction, Electron–positron annihilation, Hadron, Fermion, Standard Model, Nuclear physics, Radiative transfer, High Energy Physics::Experiment, Particle Physics - Experiment, Bhabha scattering
Abstract: Cross-sections for hadronic and leptonic two-fermion events, and leptonic forward-backward asymmetries, have been measured in e+e− collisions at a centre-of-mass energy of 161 GeV, using the OPAL detector at LEP. Results are presented both including and excluding the dominant production of radiative γZ0 events. We have measured Rb, the ratio of the number of b b to all multihadronic events at 161 GeV, and compared it to the result obtained at 130–136 GeV. All results agree well with the Standard Model expectations. In a model-independent fit to the Z0 lineshape, the data presented here give an improved precision on the γZ0-interference term. The data have also been used to obtain new limits on extensions of the Standard Model described by effective four-fermion contact interactions.

46. An upper limit on the branching ratio for τ decays into seven charged particles

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, 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, P. Berlich, 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, S. De Jong, L.A. del Pozo, K. Desch, 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, T. Hilse, P.R. Hobson, R.J. Homer, A.K. Honma, D. Horváth, R. Howard, 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, 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, K. Nagai, I. Nakamura, H.A. Neal, B. Nellen, R. Nisius, S.W. O'Neale, F.G. Oakham, F. Odorici, H.O. Ogren, N.J. Oldershaw, M.J. Oreglia, S. Orito, J. Pálinkás, G. Pásztor, J.R. Pater, G.N. Patrick, J. Patt, M.J. Pearce, S. Petzold, P. Pfeifenschneider, J.E. Pilcher, J. Pinfold, D.E. Plane, P. Poffenberger, B. Poli, A. Posthaus, H. Przysiezniak, D.L. Rees, D. Rigby, S. Robertson, S.A. Robins, N. Rodning, J.M. Roney, A. Rooke, E. Ros, A.M. Rossi, M. Rosvick, 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. Schulz, 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, 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, 010308 nuclear & particles physics, Branching fraction, Detector, FOS: Physical sciences, 01 natural sciences, Charged particle, 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, Lepton
Abstract: We have searched for decays of the tau lepton into seven or more charged particles, using data collected with the OPAL detector from 1990 to 1995 in e^+e^- collisions at sqrt(s) ~ M_Z. No candidate events were found and an upper limit on the branching ratio for tau decays into seven charged particles of 1.8 x 10^-5 at the 95% confidence level was determined., Comment: 13 pages LaTeX, uses a4p.sty, 4 eps figures included, accepted by Physics Letters B

47. Search for scalar top and scalar bottom quarks using the OPAL detector at LEP

Author: P. S. Wells, W. Matthews, M. Hapke, Claire Shepherd-Themistocleous, Terry Richard Wyatt, J. E. Bloomer, A. Joly, Stefan Kluth, M. A. Thomson, Shlomit Tarem, D. E. Hutchcroft, A. I. McNab, J. Goldberg, B. Nellen, M. Sproston, H. G. Evans, M. J. Goodrick, I. Cohen, R. Lahmann, M. J. Oreglia, D. C. Imrie, R. W. Springer, Gunter Wolf, K. Ackerstaff, S. Braibant, P. Gagnon, Silvia Arcelli, John Allison, J. Grunhaus, R. Bartoldus, C. Sbarra, S. M. Gascon-Shotkin, A. D. Schaile, Gabriella Pasztor, C. Hartmann, D. E. Plane, Dave Charlton, Paolo Giacomelli, Stephen Hillier, James Pinfold, G. W. Wilson, R. G. Kellogg, M. Steiert, G. P. Siroli, M. Hansroul, M. Hauschild, D. M. Strom, A. Sittler, S. A. Wotton, D. G. Fong, C. Lewis, N. K. Watson, H. O. Ogren, G. M. Dallavalle, J. Gascon, Csaba Hajdu, R. Bürgin, Ehud Duchovni, S. Yamashita, P. Igo-Kemenes, G. Yekutieli, C. Burgard, Christoph Geich-Gimbel, J. R. Carter, R. J. Homer, C. Markus, Alan Watson, K. Ishii, H. Jeremie, G. N. Patrick, Stefano Marcellini, H. M. Bosch, G. Giacomelli, Otmar Biebel, R. Rylko, G. A. Snow, C. P. Ward, S. Söldner-Rembold, F. Wäckerle, Sachio Komamiya, Theodoros Geralis, E. Ros, Gideon Bella, Kiyotomo Kawagoe, A. A. Carter, Ron Folman, Roger Jones, I. J. Bloodworth, G. T. Jones, W. Mohr, E. H. Vokurka, E. A. Mckigney, Matthew Evans, D. M. Gingrich, A. M. Rossi, T. Behnke, T. Tsukamoto, Eilam Gross, M. Jimack, A. Michelini, R. E. Hughes-Jones, H. J. Burckhart, J. W. Gary, Jacqueline Batley, D. S. Koetke, J. Lauber, B. J. King, Achim Stahl, W. P. Lai, Matthias Schröder, N. J. Oldershaw, B. Stockhausen, Paul Kyberd, F. K. Loebinger, O. Schaile, Satoshi Tanaka, T. Kobayashi, E. do Couto e Silva, A. Posthaus, M. Gruwé, P. Utzat, P. Berlich, Marcello Mannelli, K. Nagai, T. P. Kokott, Richard Keeler, C. M. Hawkes, D. R. Rust, Hans-Christian Schultz-Coulon, Randall Sobie, Michael Schulz, G. D. Lafferty, J. Steuerer, T. Omori, D. Rigby, R. J. Hemingway, F. Strumia, S. D. Talbot, M. Thiergen, P. Scharff-Hansen, H. Mes, U. Ruppel, J. M. Roney, Reda Tafirout, Klaus Kurt Desch, Sven Menke, J. Letts, A. M. Lee, T. J. McMahon, D. Chrisman, N. I. Geddes, Michael Hildreth, Yoram Rozen, C. R. Jones, Volker Blobel, E. von Törne, M. R. Ingram, Richard Nisius, I. P. Duerdoth, Georges Azuelos, K. Sachs, Norbert Wermes, Shlomo Dado, E. Tsur, D. L. Rees, Joleen Pater, P. Pfeifenschneider, N. L. Rodning, R. Howard, M. Foucher, Sherry Towers, T. Kawamoto, R. K. Carnegie, J. Patt, Stephen Lloyd, J. S. White, Marco Cuffiani, F. Scharf, German Martinez, M. Herndon, P. Schenk, J. E. Conboy, A. Fürtjes, Robert M Brown, B. Poli, P. Fath, M. Bobinski, J. A. Wilson, D. Karlen, Robert McPherson, Daniel Lellouch, M. Verzocchi, B. W. Kennedy, R. Giacomelli, Mathieu Doucet, Takehiko Mori, R. D. Heuer, Fabrizio Fabbri, A. M. Smith, S. Orito, V. Zacek, P. G. Estabrooks, M. Rosvick, Giora Mikenberg, H. M. Fischer, P. Jovanovic, D. Axen, Austin Ball, W. R. Gibson, K. Ametewee, A. Jawahery, M. F. Turner-Watson, K. W. Bell, J. Pálinkás, Gideon Alexander, Guenter Duckeck, D. Lazic, Paolo Capiluppi, Stefan Schmitt, Peter Krieger, M. Morii, Peter Sherwood, Peter R Hobson, P. M. Watkins, O. C. Cooke, T. J. Smith, B. T. Bouwens, M. Boutemeur, F. S. Merritt, P. Mättig, Shoji Asai, Alexander Wagner, P. Routenburg, S. A. Robins, J. Ludwig, J. C. Hill, Misao Sasaki, K. Runge, P. Bock, Lorne Levinson, J. von Krogh, A. S. Turcot, F. Fiedler, Andris Skuja, R. J. Hawkings, J. Bechtluft, J. A. McKenna, A. Skillman, S. Petzold, Manuella Vincter, U. Müller, L. A. del Pozo, Alessandro Montanari, M. Schumacher, E. Lefebvre, F. Odorici, M. Kolrep, W. J. McDonald, G. D. Long, B. C. Shen, A. J. Martin, S. B. Anderson, P. Szymanski, S. Robertson, Tetsuro Mashimo, Gregor Herten, Siegfried Bethke, Stan Bentvelsen, A. K. Honma, B. Nijjhar, W. G. Scott, B. Wilkens, I. Nakamura, J. E. Pilcher, D. Glenzinski, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, W. Gorn, C. Dallapiccola, C. K. Hargrove, Tara Shears, K. Stephens, P. A. Hart, N. Altekamp, M. J. Pearce, R. J. Barlow, D. J. Miller, V. Gibson, T. R. Junk, I. Trigger, U. Jost, R. Mir, P. Poffenberger, P. Schütz, D. R. Ward, T. Kress, F. G. Oakham, C. Y. Chang, B. Schmitt, E. L. Barberio, P. Taras, Michael Kobel, Julie Kirk, S. W. O'Neale, K. J. Anderson, M. Fierro, J. E.G. Edwards, S. R. Lautenschlager, H. A. Neal, T. Hilse, O. Runolfsson, C. Beeston, Claudio Grandi, Ekg Sarkisyan, P. W. Jeffreys, R. Kooten, J. J. Ward, P. Vikas, D. Lanske, G. G. Hanson, M. S. Dixit, Frans Meijers, A. Rooke, J. G. Layter, P. E.L. Clarke, M. K. Jones, J. P. Martin, S. De Jong, H. Przysiezniak, and A. N. Bell
Subjects: Physics, Nuclear and High Energy Physics, Top quark, Stop squark, Particle physics, High Energy Physics::Lattice, High Energy Physics::Phenomenology, Down quark, Top quark condensate, Bottom quark, Nuclear physics, Quark star, Up quark, High Energy Physics::Experiment, B meson, Particle Physics - Experiment
Abstract: The scalar top quark can be the lightest charged supersymmetric particle and it can be lighter than the top quark itself in supersymmetric extensions of the Standard Model. A search for a scalar top quark has been performed using a total data sample of 15.2 pb−1 at centre-of-mass energies of √s = 130, 136, and 161 GeV collected with the OPAL detector at LEP. No evidence was found above the background level expected from the Standard Model. The 95% C.L. lower limit on the scalar top quark mass is 58.7 GeV, if the mixing angle between the supersymmetric partners of the left- and right-handed states of the top quark is smaller than π 4 . If the mixing angle is zero, the limit is 65.4 GeV. These limits were obtained on the condition 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. Assuming a relatively light scalar neutrino, we also studied the complementary decay mode of the scalar top quark in which it decays into a bottom quark, a charged lepton, and a scalar neutrino. A mass limit on the light scalar bottom quark was also set in this study.

48. Improved measurement of the lifetime of the tau lepton

Author: M. Hapke, S. M. Gascon-Shotkin, D. E. Hutchcroft, M. J. Oreglia, P. Poffenberger, Matthew Evans, A. M. Rossi, G. W. Wilson, M. Hauschild, J. R. Carter, G. N. Patrick, P. Schütz, C. Markus, T. J. McMahon, P. Scharff-Hansen, Mathieu Doucet, R. D. Heuer, Fabrizio Fabbri, John Allison, W. J. McDonald, F. S. Merritt, B. C. Shen, Madjid Boutemeur, J. Schwiening, R. K. Carnegie, G. T. Jones, J. A. Wilson, W. Matthews, A. Gaidot, Siegfried Bethke, E. H. Vokurka, P. G. Estabrooks, Stefan Kluth, R. K. Keeler, A. M. Smith, M. A. Thomson, B. Lorazo, Shlomit Tarem, A. K. Honma, B. Nijjhar, W. G. Scott, G. Vasseur, H. M. Fischer, E. Lefebvre, A. Michelini, R. G. Kellogg, D. R. Rust, E. K. U. Gross, S. A. Robins, S. Braibant, F. Odorici, D. Rigby, R. J. Hemingway, R. Bartoldus, M. Sproston, N. Tesch, Csaba Hajdu, Stefano Marcellini, Tara Shears, Otmar Biebel, O. C. Cooke, P. Gagnon, Achim Stahl, J. Bechtluft, J. A. McKenna, P. M. Watkins, Gideon Bella, C. H. Shepherd-Themistocleous, H. J. Burckhart, Jacqueline Batley, B. W. Kennedy, P. Jovanovic, N. K. Watson, Gabriella Pasztor, Gregor Herten, J. von Krogh, N. I. Geddes, Michael Hildreth, N. L. Rodning, A. M. Lee, M. Tecchio, E. von Törne, Austin Ball, B. Poli, Peter Krieger, A. I. McNab, C. Y. Chang, B. Wilkens, P. A. Hart, James Pinfold, S. Yamashita, Sachio Komamiya, P. Igo-Kemenes, W. Mohr, D. G. Fong, C. Lewis, J. Gascon, A. Sittler, Dezso Horvath, M. J. Losty, A. Joly, G. Azuelos, J. Letts, Manuella Vincter, Alessandro Montanari, T. Omori, Norbert Wermes, J. Goldberg, Sherry Towers, T. Kawamoto, A. Posthaus, B. Nellen, G. A. Snow, C. P. Ward, B. Schmitt, J. P. Pansart, Hans-Christian Schultz-Coulon, L. A. del Pozo, C. Sbarra, H. Jeremie, R. E. Hughes-Jones, Randall Sobie, Jean-Arcady Meyer, P. Taras, U. Jost, R. Mir, Silvia Arcelli, Michael Kobel, Michael Schulz, G. D. Lafferty, J. O. Runolfsson, P. Weber, Theodoros Geralis, E. Ros, A. T. Watson, R. Kowalewski, R. Hawking, H. Mes, S. Söldner-Rembold, I. P. Duerdoth, Koji Yoshimura, J. E. Pilcher, G. Yekutieli, A. Malik, J. W. Gary, D. S. Koetke, M. J. Pearce, S. Orito, M. Rosvick, T. Behnke, C. Darling, A. Rooke, R. Howard, J. S. White, P. Fath, T. P. Kokott, H. G. Evans, M. J. Goodrick, A. A. Carter, E. do Couto e Silva, A. Luig, J. G. Layter, Marcello Mannelli, D. L. Rees, Andris Skuja, Ron Folman, Paul Kyberd, Roger Jones, S. Petzold, F. K. Loebinger, H. M. Bosch, E. A. Mckigney, K. Ametewee, J. Steuerer, Paolo Giacomelli, I. Cohen, F. Scharf, German Martinez, M. Hansroul, P. Mättig, G. D. Long, Gideon Alexander, H. Takeda, Julie Kirk, A. D. Schaile, F. G. Oakham, Tetsuro Mashimo, P. Utzat, Shoji Asai, W. P. Lai, Guenter Duckeck, R. W. Springer, Joleen Pater, Paolo Capiluppi, M. Gruwé, Sven Menke, M. G. Rison, Gunter Wolf, F. X. Gentit, Shlomo Dado, C. M. Hawkes, E. L. Barberio, Daniel Lellouch, R. Giacomelli, J. M. Roney, Dave Charlton, Takehiko Mori, A. S. Turcot, W. Gorn, O. Schaile, C. Dallapiccola, R. J. Homer, R. Bürgin, V. Zacek, R. Lahmann, D. C. Imrie, M. Palazzo, D. Axen, A. Jawahery, C. Charlesworth, Giora Mikenberg, S. Wotton, D. Chrisman, E. Tsur, Richard Nisius, Volker Blobel, N. Altekamp, M. Starks, D. M. Strom, M. Verzocchi, K. W. Bell, M. F. Turner-Watson, Peter Sherwood, Alexander Wagner, S. W. O'Neale, R. J. Barlow, D. J. Miller, M. Morii, Peter R Hobson, J. Pálinkás, Stephen Lloyd, J. C. Hill, Matthias Schröder, Marco Cuffiani, K. J. Anderson, M. Thiergen, H. Fukui, R. Rylko, J. Ludwig, K. Runge, P. Bock, J. Lauber, Misao Sasaki, P. Routenburg, S. B. Anderson, P. Szymanski, Ehud Duchovni, Stefania Xella, M. Jimack, S. L. Chu, G. P. Siroli, J. King, F. Strumia, Stan Bentvelsen, P. S. Wells, S. W. Gensler, T. Kobayashi, Terry Richard Wyatt, J. E. Bloomer, P. E.L. Clarke, M. K. Jones, J. P. Martin, M. Tscheulin, S. De Jong, U. Müller, A. J. Martin, H. Przysiezniak, A. N. Bell, I. J. Bloodworth, G. G. Hanson, C. K. Hargrove, G. Giacomelli, P. Schenk, Yoram Rozen, M. S. Dixit, Frans Meijers, M. Foucher, Junichi Kanzaki, D. Karlen, C. Burgard, B. Stockhausen, T. Wlodek, M. Fierro, J. E.G. Edwards, T. Hilse, C. Beeston, Claudio Grandi, Ekg Sarkisyan, P. W. Jeffreys, P. Bright-Thomas, J. J. Ward, P. Vikas, D. Lanske, C. Hartmann, D. E. Plane, Stephen Hillier, G. M. Dallavalle, Reda Tafirout, Frank Fiedler, M. R. Ingram, W. R. Gibson, H. O. Ogren, Christoph Geich-Gimbel, B. T. Bouwens, J. E. Conboy, A. Fürtjes, R. M. Brown, Lorne Levinson, Gilles Beaudoin, A. Skillman, R. Van Kooten, F. Wäckerle, D. M. Gingrich, T. J. Smith, K. Stephens, P. Berlich, V. Gibson, D. R. Ward, H. Lafoux, and T. Kress
Subjects: Physics, Nuclear physics, Nuclear and High Energy Physics, Electron–positron annihilation, Decay length, Impact parameter, Particle Physics - Experiment, Lepton
Abstract: A new measurement of the τ lifetime is presented. It uses data collected with the Opal detector during 1994, which almost doubles the size of the Opal τ sample. Two statistically independent techniques are used: an impact parameter analysis of one-prong decay tracks and a fit to the decay length distribution of three-prong decays. The lifetime obtained from the 1994 data by combining the results of these methods is τ τ = 289.7 ± 2.5 (stat)± 1.5 (sys) fs. When combined with the previous Opal τ lifetime measurement the improved τ lifetime is τ τ = 289.2 ± 1.7 (stat.) ± 1.2 (sys.) fs.

49. A study of four-fermion final states with high multiplicity at LEP

Author: E. Lefebvre, J. Palinkas, Shlomo Dado, F. Odorici, Giora Mikenberg, Daniel Lellouch, Takehiko Mori, Dave Charlton, Silvia Arcelli, R. Bürgin, V. Zacek, S. Yamashita, P. Igo-Kemenes, W. Matthews, H. Jeremie, R. E. Hughes-Jones, G. Giacomelli, V. Gibson, E. do Couto e Silva, P. Weber, H. Mes, Sven Menke, I. P. Duerdoth, P. Fath, M. A. Thomson, N. I. Geddes, Otmar Biebel, R. Lahmann, D. C. Imrie, M. Palazzo, E. A. Mckigney, I. J. Bloodworth, G. P. Siroli, Michael Hildreth, J. King, A. Gaidot, N. L. Rodning, Hans-Christian Schultz-Coulon, Randall Sobie, R. W. Springer, W. P. Lai, B. Poli, Michael Schulz, S. Braibant, Gabriella Pasztor, Gunter Wolf, G. A. Snow, C. P. Ward, D. Axen, A. Jawahery, S. Söldner-Rembold, Gideon Bella, R. Kowalewski, T. Wlodek, M. Sproston, Yoram Rozen, M. Foucher, Peter Sherwood, Junichi Kanzaki, C. H. Shepherd-Themistocleous, D. Karlen, C. Burgard, Alexander Wagner, J. Ludwig, K. Runge, J. M. Roney, H. J. Burckhart, Jacqueline Batley, H. M. Fischer, A. Michelini, P. Bock, J. Letts, K. Stephens, Reda Tafirout, T. Hilse, Norbert Wermes, Sherry Towers, T. Kawamoto, C. Darling, T. J. Smith, S. A. Robins, T. Omori, N. Tesch, P. Gagnon, S. Orito, M. Rosvick, Georges Azuelos, S. Wotton, J. Allison, G. D. Lafferty, P. Mättig, Shoji Asai, E. Tsur, Guenter Duckeck, M. Hapke, O. Runolfsson, A. Sittler, A. Joly, C. M. Hawkes, M. Verzocchi, J. R. Carter, H. M. Bosch, K. W. Bell, M. J. Oreglia, A. I. McNab, J. Lauber, J. Goldberg, S. M. Gascon-Shotkin, R. Bartoldus, H. O. Ogren, Madjid Boutemeur, N. K. Watson, Christoph Geich-Gimbel, J. C. Hill, Misao Sasaki, G. N. Patrick, B. Nellen, F. Strumia, Claudio Grandi, W. J. McDonald, B. C. Shen, A. S. Turcot, K. Ametewee, Matthew Evans, A. M. Rossi, P. G. Estabrooks, F. X. Gentit, Siegfried Bethke, C. Y. Chang, A. K. Honma, W. G. Scott, H. G. Evans, J. E. Conboy, A. Fürtjes, M. J. Goodrick, W. Mohr, I. Cohen, C. Hartmann, D. E. Plane, Stephen Hillier, A. Posthaus, P. M. Watkins, D. J. Miller, Gideon Alexander, G. M. Dallavalle, F. S. Merritt, T. R. Wyatt, Paolo Capiluppi, Dezso Horvath, M. J. Losty, Jean-Arcady Meyer, S. B. Anderson, Koji Yoshimura, R. J. Barlow, Alan Watson, P. Szymanski, Stefan Kluth, P. Taras, Shlomit Tarem, M. Fierro, J. E.G. Edwards, Ekg Sarkisyan, D. L. Rees, Michael Kobel, P. W. Jeffreys, F. Scharf, German Martinez, W. R. Gibson, J. Bechtluft, B. T. Bouwens, M. F. Turner-Watson, J. A. McKenna, A. D. Schaile, M. Morii, Stan Bentvelsen, R. G. Kellogg, D. Chrisman, Peter R Hobson, Volker Blobel, Csaba Hajdu, J. J. Ward, P. Vikas, Lorne Levinson, Julie Kirk, Stefano Marcellini, D. Lanske, Gilles Beaudoin, A. Skillman, J. W. Gery, Stephen Lloyd, Robert M Brown, D. R. Ward, B. Stockhausen, Paul Kyberd, P. Routenburg, F. K. Loebinger, T. Kress, J. Steuerer, Ehud Duchovni, Joleen Pater, Sachio Komamiya, M. Jimack, Theodoros Geralis, E. Ros, R. Giacomelli, S. W. Gensler, T. Kobayashi, S. W. O'Neale, K. J. Anderson, P. Poffenberger, T. P. Kokott, A. Luig, P. Schütz, P. S. Wells, Gregor Herten, J. E. Bloomer, B. Wilkens, Frank Fiedler, Paolo Giacomelli, J. E. Pilcher, M. Hansroul, M. R. Ingram, D. M. Strom, H. Fukui, R. Rylko, O. Schaile, M. Starks, James Pinfold, G. W. Wilson, M. Hauschild, D. G. Fong, C. Lewis, C. Markus, G. T. Jones, J. Gascon, E. H. Vokurka, Richard Keeler, R. J. Homer, R. Howard, J. S. White, J. P. Pansart, A. Malik, Mathieu Doucet, D. S. Koetke, Marcello Mannelli, C. Sbarra, R. D. Heuer, P. Scharff-Hansen, Fabrizio Fabbri, Achim Stahl, G. Yekutieli, A. M. Smith, A. A. Carter, G. Vasseur, P. E.L. Clarke, B. Lorazo, M. K. Jones, J. P. Martin, Ron Folman, Roger Jones, R. Van Kooten, M. Tscheulin, Andris Skuja, S. Petzold, G. D. Long, S. De Jong, Tetsuro Mashimo, P. Utzat, D. E. Hutchcroft, C. Dallapiccola, H. Przysiezniak, M. G. Rison, A. N. Bell, U. Müller, T. J. McMahon, W. Gorn, J. Schwiening, R. K. Carnegie, A. J. Martin, J. A. Wilson, A. Rooke, J. G. Layter, C.J. Beeston, B. Schmitt, N. Altekamp, C. Charlesworth, O. C. Cooke, Stefania Xella, J. von Krogh, G. G. Hanson, C. K. Hargrove, F. Wäckerle, R. J. Hawkings, Matthias Schröder, M. Thiergen, H. Lafoux, L. A. del Pozo, P. Schenk, M. S. Dixit, Frans Meijers, D. M. Gingrich, Tara Shears, P. A. Hart, B. Nijjhar, M. J. Pearce, D. Rigby, R. J. Hemingway, B. W. Kennedy, P. Berlich, P. Jovanovic, Austin Ball, Peter Krieger, D. R. Rust, S. L. Chu, Manuella Vincter, Alessandro Montanari, A. M. Lee, U. Jost, R. Mir, M. Tecchio, E. von Törne, H. Takeda, F. G. Oakham, E. L. Barberio, T. Behnke, Eilam Gross, M. Gruwé, Richard Nisius, and Marco Cuffiani
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Luminosity (scattering theory), Monte Carlo method, High Energy Physics::Experiment, Fermion, High multiplicity, Atomic physics, Resonance (particle physics), Particle Physics - Experiment, Lepton, Standard Model
Abstract: A search for l + l − q q (l = e, μ) four-fermion final states in high multiplicity events has been performed at s ≈m Z and above the Z peak at s =130 GeV and s =136 GeV. The data taken with OPAL correspond to an integrated luminosity of 132.4 pb−1 and 5.3 pb−1 at s ≈m Z and s =130−136 GeV, respectively. While at the Z resonance the data are in good agreement with the Standard Model predictions, we find more events than expected at s =130−136 GeV, especially in the μ + μ − q q channel, where 5 events remain after all cuts, with only 0.6 predicted by the Monte Carlo simulation. For all center-of-mass energies the observed shapes of the differential distributions are consistent with the predictions.

50. Measurement of the longitudinal cross-section using the direction of the thrust axis in hadronic events 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, 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, D.E. Hutchcroft, 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: Quantum chromodynamics, Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, Detector, Hadron, Monte Carlo method, High Energy Physics::Phenomenology, FOS: Physical sciences, Parton, Thrust, 01 natural sciences, Gluon, High Energy Physics - Experiment, Cross section (physics), High Energy Physics - Experiment (hep-ex), 0103 physical sciences, High Energy Physics::Experiment, 010306 general physics, Particle Physics - Experiment
Abstract: In the process e+e- to hadrons, one of the effects of gluon emission is to modify the 1+cos(theta)**2 form of the angular distribution of the thrust axis, an effect which may be quantified by the longitudinal cross-section. Using the OPAL detector at LEP, we have determined the longitudinal to total cross-section ratio to be 0.0127+-0.0016+-0.0013 at the parton level, in good agreement with the expectation of QCD computed to Order(alpha_s**2) Comparisions at the hadron level with Monte Carlo models are presented. The dependence of the longitudinal cross-section on the value of thrust has also been studied, and provides a new test of QCD., 16 pages, LaTeX, 4 eps figures and 3 colour eps figs included, submitted to Phys. Lett. B

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Database

Publisher

52 results on '"M Thiergen"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources