22-28 July 2010
Palais des Congrès de Paris
Europe/Paris timezone

Direct Photons at HERA

24 Jul 2010, 09:20
Salle 252B ()

Salle 252B

Parallel Session Talk 03 - Perturbative QCD, Jets and Diffractive Physics 03 - Perturbative QCD, Jets and Diffractive Physics


Juan Terron (DESY)


The production of prompt photons is measured in the photoproduction regime of electron-proton scattering at HERA. Cross sections are measured for photons with transverse momentum and pseudorapidity in the range 6 < Et < 15 GeV and -1.0 < eta < 2.4, respectively. The results are compared with QCD predictions based on the collinear and on the k_T factorisation approaches. The first measurement of diffractive scattering of quasi-real photons with large momentum transfer gamma p -> gamma Y, where Y is theproton dissociative system, is made using the H1 detector at HERA. The measurement is performed for initial photon virtualities Q^2 < 0.01 GeV^2.The W dependence is well described by a model based on perturbative QCD using a leading logarithmic approximation of the BFKL evolution. New measurements of elastic deeply virtual Compton scattering gamma* p -> gamma p using e^+ p and e^- p collision data recorded with the H1 and ZEUS detectors at HERA (full stat) are also presented.

Primary authors

Dr Katja Krueger (DESY/Heidelberg) Dr Tobias Haas (DESY)

Presentation Materials