ATLAS

Abstract:

Inclusive jet differential cross sections for the reaction ep → jet + X at Q2below 4 GeV2have been measured with the ZEUS detector at HERA using an integrated luminosity of 0.55 pb-1. These cross sections are given in the kinematic region 0.2 < y < 0.85, for jet pseudorapidities in the ep-laboratory range -1 < ηjet< 2 and refer to jets at the hadron level with a cone radius of one unit in the η - θ plane. These results correspond to quasi-real photoproduction at centre-of-mass energies in the range 130-270 GeV and, approximately, for jet pseudorapidities in the interval -3 < ηjet(λp CMS) < 0. These measurements cover a new kinematic regime of the partonic structure of the photon, at typical scales up to ∼300 GeV2and photon fractional momenta down to xγ∼ 10-2. Leading logarithm parton shower Monte Carlo calculations, which include both resolved and direct processes and use the predictions of currently available parametrisations of the photon parton distributions, describe in general the shape and magnitude of the measured ηjetand Etjetdistributions. © 1995.

Abstract:

We report a measurement of the inclusive muon and b-quark production cross sections in pp» collisions at s=1.8 TeV using the D0 detector at the Fermilab Tevatron collider. The inclusive muon spectrum extends over the kinematic range | y|<0.8 and 3.56GeV/c is extracted, and agrees with next-to-leading order QCD predictions within the experimental and theoretical uncertainties. © 1995 The American Physical Society.

Abstract:

We performed a direct search for the anomalous ZZ and Z couplings by studying pp» +X (=e,) events at s=1.8 TeV with the D0 detector at the Fermilab Tevatron Collider. A fit to the transverse energy spectrum of the photon in the signal events, based on the data set corresponding to an integrated luminosity of 14.3 pb-1 (13.7 pb-1) for the electron (muon) channel, yields the following 95% confidence level limits on the anomalous CP-conserving ZZ couplings: |h30Z|<1.8 (h40Z=0) and |h40Z|<0.5 (h30Z=0), for a form-factor scale =500 GeV. Limits for the Z couplings and CP-violating couplings are also discussed. © 1995 The American Physical Society.

Abstract:

Deep inelastic e-p scattering has been studied in both the charged current (CC) and neutral current (NC) reactions at momentum transfers squared Q2 above 400 GeV2 using the ZEUS detector at the HERA ep collider. The CC and NC total cross sections, the NC to CC cross section ratio, and the differential cross sections d/dQ2 are presented. From the Q2 dependence of the CC cross section, the mass term in the CC propagator is determined to be MW=76 16 13 GeV. © 1995 The American Physical Society.