The photoproduction of D ∗± mesons has been measured with the ZEUS detector at HERA at three different ep centre-of-mass energies, \( \sqrt{s} \), of 318, 251 and 225 GeV. For each data set, D ∗± mesons were required to have transverse momentum, p T D ∗ , and pseudo-rapidity, η D∗, in the ranges 1.9 < p T D ∗ < 20 GeV and |η D∗| < 1.6. The events were required to have a...
Photoproduction of beauty and charm quarks in events with at least two jets has been measured with the ZEUS detector at HERA using an integrated luminosity of 133 pb−1. The fractions of jets containing b and c quarks were extracted using the invariant mass of charged tracks associated with secondary vertices and the decay-length significance of these vertices. Differential cross...
. Wolfe,55 K. Wrona,15 A.G. Yagues-Molina,15 S. Yamada,24 Y. Yamazaki,24,z R. Yoshida,1 C. Youngman,15 A.F. Zarnecki,52 L. Zawiejski,12 O. Zenaiev,26 W. Zeuner,15,n B.O. Zhautykov,25 N. Zhmak,26,aa C. Zhou
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, Q 2, between 125 and 20 000 GeV2. The jets were reconstructed with the k T cluster algorithm in the Breit...
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...
The proton-dissociative diffractive photoproduction of J/ψ mesons has been studied in ep collisions with the ZEUS detector at HERA using an integrated luminosity of 112 pb−1. The cross section is presented as a function of the photon-proton centre-of-mass energy and of the squared four-momentum transfer at the proton vertex. The results are compared to perturbative QCD calculations.