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arXiv · hep-ex/0307015

Multi-Electron Production at High Transverse Momenta in ep Collisions at HERA

H1 Collaboration
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Abstract

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 \pm 0.04 and 0.23 \pm 0.04, respectively.

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H1 Collaboration. 2003-07-07. Multi-Electron Production at High Transverse Momenta in ep Collisions at HERA. https://doi.org/10.1140/epjc%2Fs2003-01326-x

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