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17 results on '"Cords, D."'

1. Energy carried by gamma rays and neutral particles in multihadron final states at petra

Author

Bartel, W., Cords, D., Dittmann, P., Eichler, R., Felst, R., Haidt, D., Krehbiel, H., Naroska, B., O'Neill, L. H., Steffen, P., Wenninger, H., Zhang, Y., Elsen, E., Helm, M., Petersen, A., Warming, P., Weber, G., Bethke, S., Drumm, H., Heintze, J., Heinzelmann, G., Hellenbrand, K. H., Heuer, R. D., von Krogh, J., Lennert, P., Kawabata, S., Matsumura, H., Nozaki, T., Olsson, J., Rieseberg, H., Wagner, A., Bell, A., Foster, F., Hughes, G., Wriedt, H., Allison, J., Ball, A. H., Bamford, G., Barlow, R., Bowdery, C., Duerdoth, I. P., Hassard, J. F., King, B. T., Loebinger, F. K., Macbeth, A. A., McCann, H., Mills, H. E., Murphy, P. G., Prosper, H. B., Stephens, K., Clarke, D., Goddard, M. C., Marshall, R., Pearce, G. F., Imori, M., Kobayashi, T., Komamiya, S., Koshiba, M., Minowa, M., Nozaki, M., Orito, S., Sato, A., Suda, T., Takeda, H., Totsuka, Y., Watanabe, Y., Yamada, S., and Yanagisawa, C.

Abstract

The fraction of the total available energy carried by photons and the fraction carried by neutral particles of all types ine+e- multihadron final states have been measured at three centre-of-mass energies between 12 and 35 GeV. These fractions are approximately 27% and 37% with no strong dependence on centre-of-mass energy and the event topology. The neutrino energy fraction is estimated to be less than 10% at the 95% confidence level.

Published
1981
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2. Studies of jet production rates ine+e− annihilation atEcm=29 GeV

Author

Bethke, S., Abrams, G., Adolphsen, C. E., Akerlof, C., Alexander, J. P., Alvarez, M., Baden, A. R., Ballam, J., Barish, B. C., Barklow, T., Barnett, B. A., Bartelt, J., Blockus, D., Bonvicini, G., Boyarski, A., Boyer, J., Brabson, B., Breakstone, A., Brom, J. M., Bullos, F., Burchat, P. R., Burke, D. L., Butler, F., Calvino, F., Cence, R. J., Chapman, J., Cords, D., Coupal, D. P., DeStaebler, H. C., Dorfan, D. E., Dorfan, J. M., Drell, P. S., Feldman, G. J., Fernandez, E., Field, R. C., Ford, W. T., Fordham, C., Frey, F., Fujino, D., Gan, K. K., Gidal, G., Glanzman, T., Goldhaber, G., Green, A., Grosse-Wiesmann, P., Haggerty, J., Hanson, G., Harr, R., Harris, F. A., Hawkes, C. M., Hayes, K., Herrup, D., Heusch, C. A., Himel, T., Hoenk, M., Hutchinson, D., Hylen, J., Innes, W. R., Jaffre, M., Jaros, J. A., Juricic, I., Kadyk, J. A., Karlen, D., Kent, J., Klein, S. R., Komamiya, S., Koska, W., Kozanecki, W., Lankford, A. J., Larsen, R. R., Levi, M. E., Li, Z., Litke, A. M., Lüth, V., Matthews, J. A. J., Meyer, D. I., Milliken, B. D., Moffeit, K. C., Müller, L., Nash, J., Nelson, M. E., Nitz, D., Ogren, H., O'Shaughnessy, K. F., Parker, S. I., Peck, C., Petersen, A., Petradza, M., Porter, F. C., Rankin, P., Riles, K., Rust, D. R., Sadrozinski, H. F. W., Schalk, T. L., Schmidke, W. B., Schwarz, A. S., Seiden, A., Smith, J. G., Snyder, A., Soderstrom, E., Stoker, D. P., Stroynowski, R., Thun, R., Trilling, G. H., Tschirhart, R., Van Kooten, R., Veltman, H., Voruganti, P., Wagner, S. R., Weber, P., Weinstein, A. J., Weir, A. J., Weisz, S., White, S. L., Wicklund, E., Wood, D. R., and Wu, D. Y.

Abstract

Production rates of multijet hadronic final states are studied ine+e- annihilation at 29 GeV center of mass energy. QCD shower model calculations with exact first order matrix element weighting at the first gluon vertex are capable of reproducing the observed multijet event rates over a large range of jet pair masses. The method used to reconstruct jets is well suited for directly comparing experimental jet rates with parton rates calculated in perturbative QCD. Evidence for the energy dependene of as is obtained by comparing the observed production rates of 3-jet events with results of similar studies performed at higher center of mass energies.

Published
1989
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3. Lepton pair production in double tagged two-photon interactions

Author

Bartel, W., Becker, L., Cords, D., Felst, R., Haidt, D., Knies, G., Krehbiel, H., Laurikainen, P., Magnussen, N., Meinke, R., Naroska, B., Olsson, J., Schmidt, D., Steffen, P., Dietrich, G., Hagemann, J., Heinzelmann, G., Kado, H., Kawagoe, K., Kleinwort, C., Kuhlen, M., Petersen, A., Ramcke, R., Schneekloth, U., Weber, G., Ambrus, K., Bethke, S., Dieckmann, A., Elsen, E., Heintze, J., Hellenbrand, K. H., Komamiya, S., von Krogh, J., Lennert, P., Matsumura, H., Rieseberg, H., Spitzer, J., Wagner, A., Bowdery, C., Finch, A., Foster, F., Hughes, G., Nye, J., Allison, J., Ball, A. H., Barlow, R. J., Chrin, J., Duerdoth, I. P., Greenshaw, T., Hill, P., Loebinger, F. K., Macbeth, A. A., Mills, H. E., Murphy, P. G., Stephens, K., Warming, P., Glasser, R. G., Skard, J. A. J., Wagner, S. R., Zorn, G. T., Cartwright, S. L., Clarke, D., Marshall, R., Middleton, R. P., Kawamoto, T., Kobayashi, T., Minowa, M., Takeda, H., Takeshita, T., and Yamada, S.

Abstract

Lepton pair production by two-photon processes has been studied using the JADE detector at PETRA. The study probed QED to a4 in the highestQ2 region. Both electrons and positrons were tagged by the endcap or barrel shower counters. The observed events consist of two produced leptons as well as two tagged electrons. These events show good agreement with QED to order a4.

Published
1986
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4. Tests of the standard model in leptonic reactions at PETRA energies

Author

Bartel, W., Becker, L., Cords, D., Felst, R., Haidt, D., Knies, G., Krehbiel, H., Laurikainen, P., Magnussen, N., Meinke, R., Naroska, B., Olsson, J., Schmidt, D., Steffen, P., Dietrich, G., Hagemann, J., Heinzelmann, G., Kado, H., Kawagoe, K., Kleinwort, C., Kuhlen, M., Petersen, A., Ramcke, R., Schneekloth, U., Weber, G., Ambrus, K., Bethke, S., Dieckmann, A., Elsen, E., Heintze, J., Hellenbrand, K. H., Komamiya, S., von Krogh, J., Lennert, P., Matsumura, H., Rieseberg, H., Spitzer, J., Wagner, A., Bowdery, C., Finch, A., Foster, F., Hughes, G., Nye, J., Allison, J., Ball, A. H., Barlow, R. J., Chrin, J., Duerdoth, I. P., Greenshaw, T., Hill, P., Loebinger, F. K., Macbeth, A. A., Mills, H. E., Murphy, P. G., Stephens, K., Warming, P., Glasser, R. G., Skard, J. A. J., Wagner, S. R., Zorn, G. T., Cartwright, S. L., Clarke, D., Marshall, R., Middleton, R. P., Kawamoto, T., Kobayashi, T., Takeda, H., Takeshita, T., and Yamada, S.

Abstract

An analysis of the three leptonic reactionse+e-?e+e-,µ+µ- andt+t- over a wide range of energy, " is presented. The data were obtained with the JADE detector at thee+e- storage ring PETRA. They are compared to predictions of electroweak theories, in particular the standard model. For the total cross-sections of all three reactions and for the differential cross-section of Bhabha scattering no deviation from QED is found over the entire energy range. The differential cross-sections of µ and t pairs at high energies show the angular asymmetry predicted by electroweak interference. The axial-vector and vector weak coupling constant, sin2?W andMZ are determined and compared to other measurements. Finally, limits on deviations from the standard model are given.

Published
1986
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5. A search for the supersymmetric chargino ine+e− annihilation at PETRA

Author

Bartel, W., Becker, L., Cords, D., Felst, R., Haidt, D., Knies, G., Krehbiel, H., Laurikainen, P., Magnussen, N., Meinke, R., Naroska, B., Olsson, J., Schmidt, D., Steffen, P., Dietrich, G., Hagemann, J., Heinzelmann, G., Kado, H., Kawagoe, K., Kleinwort, C., Kuhlen, M., Meier, K., Petersen, A., Ramcke, R., Schneekloth, U., Weber, G., Ambrus, K., Bethke, S., Dieckmann, A., Elsen, E., Heintze, J., Hellenbrand, K. H., Komamiya, S., von Krogh, J., Lennert, P., Matsumura, H., Rieseberg, H., Spitzer, J., Wagner, A., Bowdery, C. K., Finch, A. J., Foster, F., Hughes, G., Nye, J. M., Allison, J., Ball, A. H., Barlow, R. J., Chrin, J., Duerdoth, I. P., Greenshaw, T., Hill, P., Loebinger, F. K., Macbeth, A. A., McCann, H., Mills, H. E., Murphy, P. G., Stephens, K., Warming, P., Glasser, R. G., Skard, J. A. J., Wagner, S. R., Zorn, G. T., Cartwright, S. L., Clarke, D., Marshall, R., Middleton, R. P., Kawamoto, T., Kobayashi, T., Minowa, M., Takeda, H., Takeshita, T., and Yamada, S.

Abstract

A search has been made for the chargino, the supersymmetric partner of theW± (or the partner of the charged Higgs bosons), ine+e- annihilation at PETRA using the JADE detector. The chargino decay modes investigated are " and " (with subsequent gluino decay "). No evidence for such events has been observed. The 95% C.L. lower limit for the chargino mass is typically 22.5 GeV, depending only slightly on the masses of other supersymmetric particles. If the chargino is stable, the lower mass limit is 21.1 GeV (95% C.L.).

Published
1985
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6. Charged particle and neutral kaon production ine+e− annihilation at PETRA

Author

Bartel, W., Becker, L., Bowdery, C., Cords, D., Eichler, R., Felst, R., Haidt, D., Krehbiel, H., Naroska, B., Olsson, J., Steffen, P., Warming, P., Dietrich, G., Elsen, E., Heinzelmann, G., Kado, H., Meier, K., Petersen, A., Schneekloth, U., Weber, G., Bethke, S., Dieckmann, A., Heintze, J., Hellenbrand, K. H., Heuer, R. D., Kawabata, S., Komamiya, S., von Krogh, J., Lennert, P., Matsumura, H., Rieseberg, H., Wagner, A., Finch, A., Foster, F., Hughes, G., Nozaki, T., Wriedt, H., Allison, J., Ball, A. H., Bamford, G., Barlow, R., Duerdoth, I. P., Glendinning, I., Loebinger, F. K., Macbeth, A. A., McCann, H., Mills, H. E., Murphy, P. G., Rowe, P., Stephens, K., Clarke, D., Marshall, R., Pearce, G. F., Whittaker, J. B., Kanzaki, J., Kobayashi, T., Koshiba, M., Minowa, M., Nozaki, M., Odaka, S., Orito, S., Sato, A., Takeda, H., Totsuka, Y., Watanabe, Y., Yamada, S., and Yanagisawa, C.

Abstract

The mean charged multiplicity as well as its distribution has been measured as a function of c.m. energy in the reactione+e-?hadrons. Fragmentation models are compared with the data. After applying radiative corrections the mean charged multiplicity is measured to be 8.4±0.3±0.6 at 12 GeV, 13.1±0.3±0.6 at 30 GeV and 13.6±0.3±0.6 at 35 GeV. The ratio of mean charged multiplicity to the dispersion (ch>/Dch) is almost constant in the energy range studied, indicating KNO scaling of the charged multiplicity. The inclusive differential cross sections(ds/dxp) shows scaling violation in the highxp region (xp>0.15). The absolute value of the scaling violation is consistent with the result of 2nd order QCD calculations. The production of neutral kaons has been investigated by identifying the decayKS0?p+p-. The production probability for a strange quark relative to that of au ord quark in the fragmentation, ?s, has been determined to be 0.27±0.03±0.05 averaged over c.m. energies from 12 to 35 GeV. Momentum spectra for neutral kaons are presented and are compared with model predictions.

Published
1983
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7. Results from DASP one+e− annihilation between 3.1 and 5.2 GeV

Author

Brandelik, R., Braunschweig, W., Martyn, H. -U., Sander, H. G., Schmitz, D., Sturm, W., Wallraff, W., Cords, D., Felst, R., Fries, R., Gadermann, E., Hultschig, H., Joos, P., Koch, W., Kötz, U., Krehbiel, H., Kreinick, D., Lynch, H. L., McNeely, W. A., Mikenberg, G., Moffeit, K. C., Notz, D., Schliwa, M., Shapira, A., Wiik, B. H., Wolf, G., Ludwig, J., Mess, K. H., Petersen, A., Poelz, G., Ringel, J., Römer, O., Rüsch, R., Sauerberg, K., Schmüser, P., de Boer, W., Buschhorn, G., Fues, W., von Gagern, Ch., Grindhammer, G., Gunderson, B., Kotthaus, R., Lierl, H., Oberlack, H., Orito, S., Suda, T., Totsuka, Y., and Yamada, S.

Abstract

This paper summarizes the measurements one+e- annihilation performed by the DASP Collaboration in the energy range between 3.1 and 5.2 GeV. The following topics are covered: total cross section, production and two body decays of the narrow resonances, radiative decays of theJ/? and ?' resonances and evidence for theX(2.82), ?' cascade decays, inclusive ? production and evidence for theF meson, semileptonic decays of charmed mesons and properties of the heavy lepton.

Published
1979
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8. Electroproduction of π+n, π-p andK+Λ,K+2211;0 final states above the resonance region

Author

Brauel, P., Canzler, T., Cords, D., Felst, R., Grindhammer, G., Helm, M., Kollmann, W. -D., Krehbiel, H., and Schädlich, M.

Abstract

The reactionsΣvp→π+n,K+Λ,K+∑0 andΣvn→π+n were studied at invariant hadronic masses around 2.2. GeV forQ2=0.06, 0.28, 0.70, and 1.35 GeV2. The main results are: At small |t| the π+ production is dominated by longitudinally polarized photons and can be described by one pion exchange. At low |t| the transverse (π+n) cross section drops steeply withQ2, but remains roughly constant forQ2≧0.5 GeV2. For |t⊢≧0.8 GeV2, (π+n/dt) is almost independent ofQ2. The integrated cross section (π+n) shows a similarQ2-dependence asσtot (γvp) forQ2≧0.28 GeV2. The ratioσ(π-p)/σ(π+n) atQ2=0.70 and 1.35 GeV2 for |t|≧0.6 GeV2 is smaller than in photoproduction and close to 1/4. The ratioσ(K+∑0 decreases steeply withQ2 following roughly the predictions of the quark-parton model.

Published
1979
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10. Particle distribution in 3-jet events produced bye−e−-annihilation

Author

Bartel, W., Becker, L., Bowdery, C., Cords, D., Eichler, R., Felst, R., Haidt, D., Krehbiel, H., Naroska, B., Olsson, J., Steffen, P., Warming, P., Dietrich, G., Elsen, E., Heinzelmann, G., Kado, H., Meier, K., Petersen, A., Schneekloth, U., Weber, G., Bethke, S., Dieckmann, A., Heintze, J., Hellenbrand, K. H., Heuer, R. D., Komamiya, S., von Krogh, J., Lennert, P., Matsumura, H., Rieseberg, H., Spitzer, J., Wagner, A., Bell, A., Finch, A., Foster, F., Hughes, G., Nozaki, T., Wriedt, H., Allison, J., Baines, J., Ball, A. H., Barlow, R. J., Chrin, J., Duerdoth, I. P., Glendinning, I., Loebinger, F. K., Macbeth, A. A., McCann, H., Mills, H. E., Murphy, P. G., Rowe, P. G., Stephens, K., Clarke, D., Marshall, R., Pearce, G. F., Whittaker, J. B., Kanzaki, J., Kawamoto, T., Kobayashi, T., Koshiba, M., Minowa, M., Nozaki, M., Odaka, S., Orito, S., Sato, A., Takeda, H., Takeshita, T., Totsuka, Y., and Yamada, S.

Abstract

We have studied the distribution of particles within and between jets of 3-jet final states produced in the reactione+e-?hadrons at c.m. energies of 22 GeV and 29–36.4 GeV. The lowest energy jet shows distributions of transverse momenta, particle flow, and energy flow which differ significantly from those of the other two jets and from jets of 2-jet events atEcm=14 GeV. First order QCD calculations with subsequent fragmentation of quarks and gluons into hadrons indicate that the lowest energy jet has the largest probability of originating from a gluon. To reproduce the observed differences in an independent parton fragmentation model, the secondary quarks of a gluon jet have to have higher transverse momenta and lower parallel momenta than those of a quark jet. The particle densities between the jets as well as the correlation of transverse and longitudinal momenta of the particles within the jets favour models with fragmentation along the colour axes.

Published
1983
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11. Search for fractional charge and heavy stable particles at PETRA

Author

Bartel, W., Canzler, T., Cords, D., Dittmann, P., Eichler, R., Felst, R., Haidt, D., Kawabata, S., Krehbiel, H., Naroska, B., O'Neill, L., Olsson, J., Steffen, P., Yen, W., Elsen, E., Helm, M., Petersen, A., Warming, P., Weber, G., Drumm, H., Heintze, J., Heinzelmann, G., Heuer, R., Krogh, J., Lennert, P., Matsumura, H., Nozaki, T., Riesenberg, H., Wagner, A., Darwill, D., Foster, F., Hughes, G., Wriedt, H., Allison, J., Ball, A., Duerdoth, I., Hassard, J., Loebinger, F., McCann, H., King, B., Macbeth, A., Mills, H., Murphy, P., Prosper, H., Stephens, K., Clarke, D., Goddard, M., Marshall, R., Pearce, G., Imori, M., Kobayashi, T., Komamiya, S., Koshiba, M., Minowa, M., Orito, S., Sato, A., Suda, T., Takeda, H., Totsuka, Y., Watanabe, Y., Yamada, S., and Yanagisawa, C.

Abstract

A search has been made for new particles with chargeQ=2/3, 1, 4/3, 5/3 produced ine+e−-reactions at PETRA. The energy range wasEcm=27–35 GeV. No such particles were found. Upper limits for the cross-section depending on the assumed mass and production spectrum are given. ForQ=2/3 quarks with mass less than 12 GeV/c2, upper limits " (90% C.L.) are obtained both for inclusive and exclusive production. For the lifetime of theB-meson (mB=5GeV/c2) an upper limit τ≦2×10−9s is obtained.

Published
1980
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12. Measurement of the processese+e−→e+e− ande+e−→γγ at PETRA

Author

Bartel, W., Becker, L., Bowdery, C., Cords, D., Eichler, R., Felst, R., Haidt, D., Krehbiel, H., Naroska, B., Olsson, J., Steffen, P., Warming, P., Dietrich, G., Elsen, E., Heinzelmann, G., Kado, H., Meier, K., Petersen, A., Schneekloth, U., Weber, G., Bethke, S., Dieckmann, A., Heintze, J., Hellenbrand, K. H., Heuer, R. D., Komamiya, S., von Krogh, J., Lennert, P., Matsumura, H., Rieseberg, H., Wagner, A., Bell, A., Finch, A., Foster, F., Hughes, G., Nozaki, T., Wriedt, H., Allison, J., Ball, A. H., Bamford, G., Barlow, R., Duerdoth, I. P., Glendinning, I., Loebinger, F. K., Macbeth, A. A., McCann, H., Mills, H. E., Murphy, P. G., Rowe, P., Stephens, K., Clarke, D., Marshall, R., Pearce, G. F., Whittaker, J. B., Kanzaki, J., Kawamoto, T., Kobayashi, T., Koshiba, M., Minowa, M., Nozaki, M., Odaka, S., Orito, S., Sato, A., Takeda, H., Takeshita, T., Totsuka, Y., Watanabe, Y., Yamada, S., and Yanagisawa, C.

Abstract

Cross sections for the reactionse+e−→e+e− (Bhabha scattering) ande+e−→γγ are measured for center-of-mass (c.m.) energies " between 12.0 and 34.6 GeV. The results agree with the predictions of Quantum Electrodynamics (QED) and the cut-off parameters are determined. From Bhabha scattering at the highest energy, ", the 1 δ limits 0.122 ϑw<0.38 are obtained for the weak mixing angle. The higher order (α3) QED processese+e−→e+e−γ ande+e−→γγγ are also studied and are found to agree with the α3 QED predictions. A search for excited electrons is carried out by investigating the (e±γ) invariant mass distribution in the reactione+e−→e+e−γ.

Published
1983
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13. Determination of theB lifetime

Author

Bartel, W., Becker, L., Cords, D., Felst, R., Haidt, D., Knies, G., Krehbiel, H., Laurikainen, P., Magnussen, N., Meinke, R., Naroska, B., Olsson, J., Schmidt, D., Steffen, P., Dietrich, G., Hagemann, J., Heinzelmann, G., Kado, H., Kawagoe, K., Kleinwort, C., Kuhlen, M., Petersen, A., Ramcke, R., Schneekloth, U., Weber, G., Ambrus, K., Bethke, S., Dieckmann, A., Elsen, E., Heintze, J., Hellenbrand, K. H., Komamiya, S., von Krogh, J., Lannert, P., Matsumura, H., Rieseberg, H., Spitzer, J., Wagner, A., Bowdery, C., Finch, A., Foster, F., Hughes, G., Nye, J., Allison, J., Ball, A. H., Barlow, R. J., Chrin, J., Duerdoth, I. P., Greenshaw, T., Hill, P., Loebinger, F. K., Macbeth, A. A., McCann, H., Mills, H. E., Murphy, P. G., Stephens, K., Warming, P., Glasser, R. G., Skard, J. A. J., Wagner, S. R., Zorn, G. T., Cartwright, S. L., Clarke, D., Marshall, R., Middleton, R. P., Kawamoto, T., Kobayashi, T., Takeda, H., Takeshita, T., and Yamada, S.

Abstract

We have determined the lifetime ofB-hadrons produced ine+e- annihilation into multihadronic final states, by measuring the impact parameter of the track with respect to the centre of the interaction region. Two different analyses of the data were performed and gave compatible results. The lifetime is tB=1.8-0.4+0.5±0.4 ps.

Published
1986
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14. A study of photon production in hadronice+e− annihilation

Author

Bartel, W., Becker, L., Cords, D., Felst, R., Haidt, D., Junge, H., Knies, G., Krehbiel, H., Laurikainen, P., Meinke, R., Naroska, B., Olsson, J., Schmidt, D., Steffen, P., Dietrich, G., Hagemann, J., Heinzelmann, G., Kado, H., Kawagoe, K., Kleinwort, C., Kuhlen, M., Meier, K., Petersen, A., Ramcke, R., Schneekloth, U., Weber, G., Ambrus, K., Bethke, S., Dieckmann, A., Elsen, E., Heintze, J., Hellenbrand, K. H., Komamiya, S., von Krogh, J., Lennert, P., Matsumura, H., Rieseberg, H., Spitzer, J., Wagner, A., Bowdery, C., Finch, A., Foster, F., Hughes, G., Nozaki, T., Nye, J., Allison, J., Ball, A. H., Barlow, R. J., Chrin, J., Duerdoth, I. P., Greenshaw, T., Hill, P., Loebinger, F. K., Macbeth, A. A., Mills, H. E., Murphy, P. G., Stephens, K., Warming, P., Glasser, R. G., Sechi-Zorn, B., Skard, J. A. J., Wagner, S. R., Zorn, G. T., Cartwright, S. L., Clarke, D., Marshall, R., Middleton, R. P., Whittaker, J. B., Kawamoto, T., Kobayashi, T., Mashimo, T., Minowa, M., Takeda, H., Takeshita, T., and Yamada, S.

Abstract

The production of photons ine+e-??+hadrons is investigated at three centre of mass energies around 14, 22 and 34 GeV. On average, photons carry 25% of the total available energy, with a multiplicity similar to the charged multiplicity. The inclusive photon spectra are found to scale with the centre of mass energy as a function of the Feynman variablex. p0 and ? mesons are reconstructed from their decay photons. The slopes of the spectra are similar to that for charged pions and approximate scaling is observed for p0 production. The mean p0 and ? multiplicities are given. The observed photon yield can be fully accounted for by hadron decays and initial state radiation. However, up to one extra photon per event from other sources cannot be excluded.

Published
1985
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15. Measurements of energy correlations ine+e−→hadrons

Author

Bartel, W., Becker, L., Bowdery, C., Cords, D., Felst, R., Haidt, D., Junge, H., Knies, G., Krehbiel, H., Laurikainen, P., Meinke, R., Meissner, K., Naroska, B., Olsson, J., Pietarinen, E., Schmidt, D., Steffen, P., Warming, P., Zachara, M., Dietrich, G., Elsen, E., Heinzelmann, G., Kado, H., Kuhlen, M., Mashimo, T., Meier, K., Petersen, A., Schneekloth, U., Weber, G., Ambrus, K., Bethke, S., Dieckmann, A., Heintze, J., Hellenbrand, K. H., Heuer, R. D., Komaniya, S., von Krogh, J., Lennert, P., Matsumura, H., Rieseberg, H., Spitzer, J., Wagner, A., Finch, A., Foster, F., Hughes, G., Nozaki, T., Nye, J., Allison, J., Baines, J., Ball, A. H., Barlow, R. J., Chrin, J., Duerdoth, I. P., Greenshaw, T., Hill, P., Loebinger, F. K., Macbeth, A. A., McCann, H., Mills, H. E., Murphy, P. G., Stephens, K., Glasser, R. G., Sechi-Zorn, B., Skard, J. A. J., Wagner, S., Zorn, G. T., Cartwright, S. L., Clarke, D., Marshall, R., Whittaker, J. B., Kanzaki, J., Kawamoto, T., Kobayashi, T., Koshiba, M., Minowa, M., Nozaki, M., Orito, S., Sato, A., Takeda, H., Takeshita, T., Totsuka, Y., and Yamada, S.

Abstract

Energy-energy-correlations (EEC) have been measured with the JADE detector at c.m. energies of 14 GeV, 22 GeV and in the region 29 GeVcm<36 GeV. Corrected results are presented of EEC and their asymmetry, which can be directly compared to theoretical predictions. At 〈Ecm〉=34 GeV a comparison with second order QCD predictions yields good agreement for the string model fragmentation resulting in a value of the strong coupling constant αs=0.165±0.01 (stat.). The independent fragmentation models, which yield values of αs between 0.10 and 0.15 depending on the treatment of energy and momentum conservation and of the gluon splitting, do not provide a satisfactory description of the data over the full angular range.

Published
1984
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