Measurement of isolated photon production in deep inelastic ep scattering 

                       ZEUS Collaboration

                          Abstract

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. Leading-logarithm parton-shower Monte 
Carlo simulations and perturbative QCD predictions give a reasonable 
description of the data over most of the kinematic range.