20-27 July 2011
Alpes Congrès - Alpexpo
Europe/Paris timezone

J/Psi Photoproduction at HERA with ZEUS

22 Jul 2011, 15:30
Bayard (Alpes Congrès - Alpexpo)


Alpes Congrès - Alpexpo

Parallel session talk QCD


Riccardo Brugnera


The proton-dissociative diffractive photoproduction of J/psi mesons has been studied in ep collisions with the ZEUS detector at HERA using an integrated luminosity of 112 pb. The cross section is presented as a function of the photon-proton centre-of-mass energy and of the squared four-momentum transfer at the proton vertex. The results are compared to perturbative QCD calculations. The double differential inelastic J/psi photoproduction cross section as function of the squared transverse momentum of the J/psi in bins of the inelasticity z has been measured. An integrated luminosity of 468 pb-1 was used corresponding to the full data sample collected by the ZEUS experiment. The events were required to have 0.1 < z < 0.9, pt > 1 GeV and 60 < W < 240 GeV, where pt is the transverse momentum of the J/psi and W is the photon-proton centre-of-mass energy. The J/psi mesons were identified through their decay into muon pairs. The double differential cross section measurements are compared to the most recent theoretical predictions.

Primary author

Dr Aharon LEVY (Tel Aviv University)

Presentation Materials