Inclusive dijet cross sections in neutral current deep inelastic scattering at HERA
European Physical Journal C 70:4 (2010) 965-982
Abstract:
Single- and double-differential inclusive dijet cross sections in neutral current deep inelastic ep scattering have been measured with the ZEUS detector using an integrated luminosity of 374 pb-1. The measurement was performed at large values of the photon virtuality, Q2, between 125 and 20 000 GeV2. The jets were reconstructed with the kT cluster algorithm in the Breit reference frame and selected by requiring their transverse energies in the Breit frame, ET,Bjet, to be larger than 8 GeV. In addition, the invariant mass of the dijet system, Mjj, was required to be greater than 20 GeV. The cross sections are described by the predictions of next-to-leading-order QCD. © 2010 The Author(s).Measurement of high-Q2 charged current deep inelastic scattering cross sections with a longitudinally polarised positron beam at HERA
European Physical Journal C 70:4 (2010) 945-963
Abstract:
Measurements of the cross sections for charged current deep inelastic scattering in e+p collisions with a longitudinally polarised positron beam are presented. The measurements are based on a data sample with an integrated luminosity of 132 pb-1 collected with the ZEUS detector at HERA at a centre-of-mass energy of 318 GeV. The total cross section is presented at positive and negative values of the longitudinal polarisation of the positron beams. The single-differential cross-sections dσ/dQ2, dσ/dx and dσ/dy are presented for Q2>200 GeV2. The reduced cross-section σ̃ is presented in the kinematic range 200Micron size laser-wire system at the ATF extraction line, recent results and ATF-II upgrade
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment 623:1 (2010) 564-566
Abstract:
The KEK Accelerator test facility (ATF) extraction line laser-wire system has been upgraded last year allowing the measurement of micron scale transverse size electron beams. The last measurements using the upgraded system from recent operation at the ATF are presented, demonstrating raw measurements of order 3μm RMS. The main component contributions to this measurement are also discussed. © 2010 Elsevier B.V. All rights reserved.Measurement of beauty production in DIS and F2 bb̄ extraction at ZEUS: The ZEUS Collaboration
European Physical Journal C 69:3 (2010) 347-360
Abstract:
Beauty production in deep inelastic scattering with events in which a muon and a jet are observed in the final state has been measured with the ZEUS detector at HERA using an integrated luminosity of 114 pb-1. The fraction of events with beauty quarks in the data was determined using the distribution of the transverse momentum of the muon relative to the jet. The cross section for beauty production was measured in the kinematic range of photon virtuality, Q2>2 GeV2, and inelasticity, 0.05Combined measurement and QCD analysis of the inclusive e ±p scattering cross sections at HERA
Journal of High Energy Physics 2010:1 (2010)