Observation of Events at Very High Q 2 in Ep Collisions at Hera H1 Collaboration
نویسندگان
چکیده
Measurements of ep scattering with squared 4{momentum transfer Q 2 up to 35000 GeV 2 are compared with the expectation of the standard deep-inelastic model of lepton{nucleon scattering (DIS). For Q 2 > 15000 GeV 2 , N obs = 12 neutral current candidate events are observed where the expectation is N DIS = 4:71 0:76 events. In the same Q 2 range, N obs = 4 charged current candidates are observed where the expectation is N DIS = 1:77 0:87 events. The probability P(N N obs) that the DIS model signal N uctuates to N N obs in a random set of experiments is 6 10 ?3 for neutral current and 0:14 for charged current. The diierence in the observed and expected number of Neutral Current events is mostly due to events at large masses M = p x s in which the positron is backscattered at large y = Q 2 =M 2 .
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