Isolated photon production in deep inelastic ep scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 320pb-1. Measurements were made in the isolated-photon transverse-energy and pseudorapidity ranges 4 < ET < 15 GeV and -0.7 < eta < 0.9 for exchanged photon virtualities, Q2, in the range 10 < Q2 < 350 GeV and for invariant masses of the hadronic system WX > 5 GeV. Differential cross sections are presented for inclusive isolated photon production as functions of Q2, x, ET and eta. Isolated-photon+jet production in ep collisions at a centre-of-mass energy of 318 GeV has also been measured with the ZEUS detector at HERA using an integrated luminosity of up to 300 pb-1. Measurements of prompt-photon+jet cross sections are presented as functions of the photon transverse energy and pseudorapidity in a wide range of exchanged-photon virtuality. In addition, differential gamma+jet cross sections are presented as functions of the jet transverse energy and pseudorapidity. Leading-logarithm parton-shower Monte Carlo predictions and perturbative QCD calculations were compared to the data.
Dr Aharon LEVY (Tel Aviv University)