Measurement of prompt photons with associated jets in photoproduction at HERA Academic Article uri icon


  • The photoproduction of prompt photons, together with an accompanying jet, has been studied in ep collisions at a centre-of-mass energy of 318 GeV with the ZEUS detector at HERA using an integrated luminosity of 77 pb-1. Cross sections were measured for the transverse energy of the photon and the jet larger than 5 and 6 GeV, respectively. The differential +jet cross sections were reconstructed as functions of the transverse energy, pseudorapidity and xobs, the fraction of the incoming photon momentum taken by the photon-jet system. Predictions based on leading-logarithm parton-shower Monte Carlo models and next-to-leading-order (NLO) QCD generally underestimate the cross sections for the transverse energies of prompt photons below 7 GeV, while the kT-factorisation QCD calculation agrees with the data better. When the minimum transverse energy of prompt photons is increased to 7 GeV, both NLO QCD and the kT- factorisation calculations are in good agreement with the data. Springer-Verlag Berlin Heidelberg 2007.

published proceedings

  • European Physical Journal C

author list (cited authors)

  • Chekanov, S., Derrick, M., Magill, S., Miglioranzi, S., Musgrave, B., Nicholass, D., ... The ZEUS Collaboration.

citation count

  • 22

publication date

  • January 2007