Study of the colour singlet model with k_T-factorization in inclusive J/ψproduction at CERN LEP2

Abstract

We calculate the cross section and the transverse momentum distribution of inclusive J/ψproduction in γγcollisions at CERN LEP2 within the colour singlet model and the k_T-factorization approach, including both direct and resolved photon contributions. The unintegrated gluon distribution in the photon is determined, using the Blumlein's prescription for unintegrated gluon distribution in a proton. We compare our theoretical predictions with preliminary data taken by the DELPHI collaboration at LEP2. In addition, we present our predictions for the J/ψpolarization properties.

11 pages, 6 figures