Speaker
Pierre Artoisenet
(Univerite catholique de Louvain)
Description
In this talk, I review the photo-production of J/psi states at HERA. In the framework of NRQCD, I present the various components expected to contribute to the J/psi yield at HERA, and their importance in different regions of the phase space. I compare the predicted differential cross sections with the data collected by the ZEUS and H1 collaborations. I then move on the polarization observables and present the brand-new color-singlet prediction at NLO accuracy in alpha_s, in view of the recent measurement performed by the ZEUS collaboration. Based on these results, I argue that the sole color-singlet yield fails to explain the J/psi distributions measured at HERA.
Author
Pierre Artoisenet
(Univerite catholique de Louvain)
