Exclusive photoproduction of J/Ψ and Ψ′ mesons in proton-proton collisions

Abstract

We present results based on our new paper [1]. The amplitude for the γp → V p reaction is calculated in a pQCD kt-factorization approach. The corresponding total cross section for different unintegrated gluon distributions is calculated and compared with new HERA data for photon-proton collisions.We also compare the total cross section for γp → V p reaction with recent data extracted by the LHCb collaboration. The amplitude for γp → V p is used to predict cross section for exclusive photoproduction of J/ψ and ψ′ mesons in proton-proton collisions. Both Dirac and Pauli electromagnetic form factors are included in the calculation and results are compared with results when only Dirac form factor is included. The effect of Pauli form factor is quantified. Absorption effects are included and their uncertainties are discussed. Different differential distributions e.g. in J/ψ(ψ′) rapidity and transverse momentum are presented and compared with existing experimental data for the Tevatron and LHC energy.