Isolated Lepton Events at HERA ∗
نویسنده
چکیده
observed at HERA by the H1 collaboration was announced more than 10 years ago [1]. An excess of HERA I events above a priori expectations (not confirmed by ZEUS, where the analysis was performed in a more restricted phase space, see [2]) has given rise to many speculations on physics beyond the Standard Model. These events continued to appear in runs at HERA II. Both H1 and ZEUS have recently performed an analysis of the electron and muon channels (H1 also of the tau channel) on their respective complete HERA I+II data sets, which correspond to approximately 0.5 fb per experiment [3, 4]. A total of 59 events are observed in the H1 data, compared to a SM expectation of 58.9 ± 8.2. When the hadronic transverse momentum cut pT > 25 GeV is imposed, 24 events remain compared to
منابع مشابه
Searches and Electroweak Measurements at Hera
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