Photoproduction of isolated photons, inclusively and with a jet, at HERA

Abstract The photoproduction of isolated photons, both inclusive and together with a jet, has been measured with the ZEUS detector at HERAusing an integrated luminosity of 374 pb − 1 . Differential cross sections are presented in the isolated- photontransverse-energy and pseudorapidityranges 6 E T γ 15 GeV and − 0.7 η γ 0.9 , and for jet transverse-energy and pseudorapidityranges 4 E T jet 35 GeV and − 1.5 η jet 1.8 , for exchanged- photonvirtualities Q 2 1 GeV 2 . Differential cross sections are also presented for inclusive isolated- photonproduction as functions of the transverse energy and pseudorapidityof the photon. Higher-order theoretical calculations are compared to the results.