Abstract
We report on the production of low-mass electron pairs and muon pairs in p-Be collisions at 450 GeV/c at the CERN SPS. For both electron and muon pairs the low-mass spectrum can be explained satisfactorily by lepton pairs from hadronic decays, and there is no need to invoke any “unconventional” source. The normalisation of the major hadronic sources is set by the data. The upper limit, at 90% confidence level, on any new source of lepton pairs is ∼20% of the hadronic decay contribution for muons, and ∼40% for electrons.
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e + e − pairs: J. Ballam et al. Phys. Rev. Lett.41 (1978) 1207; J.H. Cobb et al. Phys. Lett.78B (1978) 519; A. Chilingarov et al. Nucl. Phys.B151 (1979) 29; R. Stroynowski et al. Phys. Lett.97B (1980) 315; S. Mikamo et al. Phys. Lett.106B (1981) 428; A.T. Goshaw et al. Phys. Rev.D24 (1981) 2829; J. Stekas et al. Phys. Rev. Lett.47 (1981) 1686; D. Blockus et al. Nucl. Phys.B201 (1982) 205; M.R. Adams et al. Phys. Rev.D27 (1983) 1977; V. Hedberg, PhD thesis, Univ. of Lund, LUNFD6/(NFFL-703)/1987, (1987) G. Roche et al. Phys. Rev. Lett.61 (1988) 1069; C. Naudet et al. Phys. Rev. Lett.62 (1989) 2652; H.Z. Huang et al. LBL Preprint 32808 (1992) 64-1 pairs: K.J. Anderson et al. Phys. Rev. Lett.37 (1976) 799; J.G. Branson et al. Phys. Rev. Lett.38 (1977) 1334; G.G. Henry, PhD thesis, Enrico Fermi Inst., Univ. Chicago (1978); H. Kasha et al. Phys. Rev. Lett.36 (1976) 1007; K. Bunnell et al. Phys. Rev. Lett.40 (1978) 136; B. Haber et al. Phys Rev.D22 (1980) 2107; J. Alspector et al. Phys. Lett.81B (1979) 397; W.M. Morse et al. Phys. Rev.D18 (1978) 3145; R.I. Dzhelyadin et al. Nucl. Phys.B179 (1981) 189; M. Faessler et al. Phys. Rev.D17 (1978) 689; D.M. Grannan et al. Phys. Rev.D18 (1978) 3150; A.V. Bannikov et al. Proceedings of the Pittsburgh Workshop on Soft Lepton Pair and Photon Production, Ed. Julia A. Thompson (Nova Science Publishers Inc., 1992), pp. 163–173. Significant results onsingle electrons or positrons include: L. Baum et al. Phys. Lett.B60 (1976) 485; A. Browman et al. Phys. Rev. Lett.37 (1976) 246; E.W. Beier et al. Phys. Rev. Lett.37 (1976) 1117; M. Barone et al. Nucl. Phys.B132 (1978) 29; Y. Makdisi et al. Phys. Rev. Lett.41 (1978) 367; R. Barloutaud et al. Nucl. Phys.B172 (1980) 25; A. Maki et al. Phys. Lett.B106 (1981) 423; T. Åkesson et al. Phys. Lett.152B (1985) 411; T. Åkesson et al. Phys. Lett.192B (1987) 463
L. Van Hove, Ann. Phys.192 (1989) 66
For a recent review see P.V. Ruuskanen JYFL-18-92 (1992); to appear in “Particle Production in Highly Excited Matter”, editor H.H. Gutbrod.
R.H. Beuttenmuller et al. NIMA252 (1986) 471
R.H. Beuttenmuller et al. NIMA253 (1987) 500
K.H. Dederichs, PhD Thesis, Chapter 3, Ludwig-Maximilians-Universität (1989)
T. Åkesson et al. NIMA262 (1987) 243
B. Dolgosheir NIMA326 (1993) 434; in particular Sect. 5.1.3
M.J. Clemen, University of Pittsburgh Thesis (1989) and Y.M. Parkm University of Pittsburgh Thesis (1990).
C.W. Fabjan et al. Paper 775 submitted to XXIV International Conference, Munich 1988; HELIOS Note 174 (1986); SSC Detector R&D at BNL, Editors Yu and Radeka, BNL 52244, (1990), 14
J. Badier et al. NIMA175 (1980) 319
R. Hammarstrom et al. NIMA176 (1980) 137
M. Morpurgo, Cryogenics19 (1979) 411
F. Gibrat, Université Paris 6 Thesis, CEA-N-2611 (1989)
R.J. Veenhof, Universiteit van Amsterdam Thesis, (1993)
C.W. Fabjan et al. NIMA216 (1983) 105
B. Alper et al. Nucl. Phys.B100 (1975) 237
M. Bourquin and J-M Gaillard Phys. Lett.59B (1975) 191 and Nucl. Phys.B114 (1976) 334
N. Kroll and W. Wada Phys. Rev.98 (1955) 1355
L.G. Landsberg, Phys. Rep.128 (1985) 301, Sect. 3.1
M. Aguilar-Benitez et al. Z. Phys.C50 (1991) 405
HELIOS/1 η→γγ in preparation.
R.I. Dzhelyadin et al. Phys. Lett.94B (1980) 548
J.G. Branson et al. Phys. Rev. Lett.38 (1977) 1331
R.I. Dzhelyadin et al. Phys. Lett.102B (1981) 296
V.A. Viktorov et al. Sov. J. Nucl. Phys.32 (1980) 520
H.U. Bengtsson and T. Sjöstrand Pythia 5.3, CERN Program Library W5045
M. Aguilar-Benitez et al. Phys. Lett.B189 (1987) 476, and Z. Phys. C.40 (1988) 321
P. Aubry, University of Montreal Thesis, (1994) and P. Pomianowski, University of Pittsburgh Thesis, (1994). Also HELIOS/1eμ and μμ events with missing energy: in preparation.
A.V. Bannikov et al. Proceedings of the Pittsburgh Workshop on Soft Lepton Pair and Photon Production, Ed. Julia A. Thompson (Nova Science Publishers Inc., 1992), pp. 163–173.
M. Diakanou et al. Phys. Lett.89B (1980) 432
S.I. Dolinsky et al. Yadernaya Fisika48 (1988) 442
J. Bartke et al. Nucl. Phys.B118 (1977) 360
R.S. Kessler et al. Phys. Rev. Lett.70 (1993) 892
P. Lichard, SUNY-NTG-94-16 (1994). We also acknowledge useful discussions with P. Lichard and J. Pišút on hadronic bremsstrahlung.
V. Černý et al. Z. Phys. C31 (1986) 163 and P. Lichard in Proceedings of the Pittsburgh Workshop on Soft Lepton Pair and Photon Production, Ed. Julia A. Thompson (Nova Science Publishers Inc., 1992), p. 61.
For example: R. Singer et al. Phys. Lett.60B (1976) 385; P.D. Higgins et al. Phys. Rev.D19 (1979) 65; M. Schouten et al. Z. Phys. C9 (1981) 93
P. Lichard, Z. Phys. C37 (1987) 125
A. Chilingarov et al. Nucl. Phys.B151 (1979) 29
T. Åkesson et al. Phys. Lett.152B (1985) 411 and T. Åkesson et al. Phys. Lett.192B (1987) 463
T. Åkesson et al. Phys. Lett.178B (1986) 447
J.A. Thompson et al. Hadron Structure 1991, p. 126, ed. L. Martinovic, Bratislava, 1991
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Åkesson, T., Almehed, S., Angelis, A.L.S. et al. Low-mass lepton-pair production in p-Be collisions at 450 GeV/c. Z. Phys. C - Particles and Fields 68, 47–64 (1995). https://doi.org/10.1007/BF01579804
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DOI: https://doi.org/10.1007/BF01579804