Multi-electron production at high transverse momenta in ep collisions at HERA

被引:25
作者
Aktas, A [1 ]
Andreev, V
Anthonis, T
Asmone, A
Babaev, A
Backovic, S
Bähr, J
Baranov, P
Barrelet, E
Bartel, W
Baumgartner, S
Becker, J
Beckingham, M
Behnke, O
Behrendt, O
Belousov, A
Berger, C
Berndt, T
Bizot, JC
Böhme, J
Boenig, MO
Boudry, V
Bracinik, J
Braunschweig, W
Brisson, V
Bröker, HB
Brown, DP
Bruncko, D
Büsser, FW
Bunyatyan, A
Buschhorn, G
Bystritskaya, L
Campbell, AJ
Caron, S
Cassol-Brunner, F
Chekelian, V
Clarke, D
Collard, C
Contreras, JG
Coppens, YR
Coughlan, JA
Cousinou, MC
Cox, BE
Cozzika, G
Cvach, J
Dainton, JB
Dau, WD
Daum, K
Delcourt, B
Delerue, N
机构
[1] Rhein Westfal TH Aachen, Inst Phys 1, D-5100 Aachen, Germany
[2] Rhein Westfal TH Aachen, Inst Phys 3, D-5100 Aachen, Germany
[3] Univ Birmingham, Sch Phys & Space Res, Birmingham B15 2TT, W Midlands, England
[4] Univ Antwerp, UIA, B-2020 Antwerp, Belgium
[5] ULB, VUB, Inter Univ Inst High Energies, Brussels, Belgium
[6] Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England
[7] Inst Phys Nucl, Krakow, Poland
[8] Univ Dortmund, Inst Phys, D-4600 Dortmund, Germany
[9] Joint Inst Nucl Res, Dubna, Russia
[10] CE Saclay, CEA, DSM, DAPNIA, Gif Sur Yvette, France
[11] DESY, D-2000 Hamburg, Germany
[12] Univ Hamburg, Inst Expt Phys, Hamburg, Germany
[13] Max Planck Inst Kernphys, D-69117 Heidelberg, Germany
[14] Univ Heidelberg, Inst Phys, D-6900 Heidelberg, Germany
[15] Univ Heidelberg, Kirchhoff Inst Phys, D-6900 Heidelberg, Germany
[16] Univ Kiel, Inst Expt & Angewandte Phys, D-24098 Kiel, Germany
[17] Slovak Acad Sci, Inst Expt Phys, Kosice 04353, Slovakia
[18] Univ Lancaster, Sch Phys Chem, Lancaster, England
[19] Univ Liverpool, Dept Phys, Liverpool L69 3BX, Merseyside, England
[20] Univ London Queen Mary & Westfield Coll, London E1 4NS, England
[21] Lund Univ, Dept Phys, Lund, Sweden
[22] Univ Manchester, Dept Phys, Manchester M13 9PL, Lancs, England
[23] Univ Mediterranee, CPPM, CNRS, IN2P3, Marseille, France
[24] Inst Theoret & Expt Phys, Moscow 117259, Russia
[25] PN Lebedev Phys Inst, Moscow 117924, Russia
[26] Max Planck Inst Phys & Astrophys, D-80805 Munich, Germany
[27] Univ Paris 11, LAL, CNRS, IN2P3, Orsay, France
[28] Ecole Polytech, LPNHE, CNRS, IN2P3, Palaiseau, France
[29] Univ Paris 06, LPNHE, CNRS, IN2P3, Paris, France
[30] Univ Paris 07, LPNHE, CNRS, IN2P3, Paris, France
[31] Acad Sci Czech Republ, Inst Phys, Prague, Czech Republic
[32] Charles Univ, Fac Math & Phys, Prague, Czech Republic
[33] Univ Roma Tre, Dipartimento Fis, Rome 3, Italy
[34] Paul Scherrer Inst, Villigen, Switzerland
[35] Berg Univ Gesamthsch Wuppertal, Fachbereich Phys, Wuppertal, Germany
[36] Yerevan Phys Inst, Yerevan 375036, Armenia
[37] DESY, Zeuthen, Germany
[38] ETH, Inst Teilchenphys, Zurich, Switzerland
[39] Univ Zurich, Inst Phys, Zurich, Switzerland
[40] Natl Tech Univ Athens, Dept Phys, GR-15773 Athens, Greece
[41] Univ Gesamthsch Wuppertal, Rechenzentrum, D-5600 Wuppertal, Germany
[42] Univ Karlsruhe, Inst Expt Kernphys, D-7500 Karlsruhe, Germany
[43] CINVESTAV, Dept Fis, Merida, Yucatan, Mexico
[44] Univ PJ Safarik, Kosice, Slovakia
[45] CERN, Geneva, Switzerland
[46] CINVESTAV, Dept Fis, Mexico City 14000, DF, Mexico
来源
EUROPEAN PHYSICAL JOURNAL C | 2003年 / 31卷 / 01期
关键词
D O I
10.1140/epjc/s2003-01326-x
中图分类号
O412 [相对论、场论]; O572.2 [粒子物理学];
学科分类号
摘要
Multi-electron production is studied at high electron transverse momentum in positron- and electron-proton collisions using the H1 detector at HERA. The data correspond to an integrated luminosity of 115 pb(-1). Di-electron and tri-electron event yields are measured. Cross sections are derived in a restricted phase space region dominated by photon-photon collisions. In general good agreement is found with the Standard Model predictions. However, for electron pair invariant masses above 100 GeV, three di-electron events and three tri-electron events are observed, compared to Standard Model expectations of 0.30 +/- 0.04 and 0.23 +/- 0.04, respectively.
引用
收藏
页码:17 / 29
页数:13
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