High-ET inclusive jet cross sections in photoproduction at HERA
The ZEUS Collaboration
J.Breitweg - et al.
Received: 11 February 1998 / Published online: 2 July 1998
Inclusive jet differential cross sections for the reaction with quasi-real photons have been measured with the ZEUS detector at HERA. These cross sections are given for the photon-proton centre-of-mass energy interval 134 <W< 277GeV and jet pseudorapidity in the range in the laboratory frame. The results are presented for three cone radii in the plane, . Measurements of above various jet-transverse-energy thresholds up to 25GeV and in three ranges of W are presented and compared to next-to-leading order (NLO) QCD calculations. For jets defined with R=1.0 differences between data and NLO calculations are seen at high and low ETjet. The measured cross sections for jets defined with R=0.7 are well described by the calculations in the entire measured range of and ETjet. The inclusive jet cross section for ETjet>21GeV is consistent with an approximately linear variation with the cone radius R in the range between 0.5 and 1.0, and with NLO calculations.