Prompt Photons in Photoproduction and Deep Inelastic Scattering at HERA

The production of isolated prompt photons is measured in photoproduction and deep-inelastic scattering (DIS) with the ZEUS and H1 detectors at HERA. The photoproduction differential cross sections measured by H1 and ZEUS are presented as a function of ETγ, ETjet, xγ and the pseudorapidities ηγ and ηjet. The DIS differential cross sections measured by H1 are presented as a function of ETγ, ηγ and Q2. Isolated photon cross sections in DIS are also measured for events with no jet or at least one hadronic jet in the final state. The measurements are compared with predictions from several MC generator models and with several next-to-leading order (NLO) Calculation.