Quarkonium production in association with a photon and nuclear effects

In this contribution we investigate the influence of nuclear effects in hadroproduction of quarkonium associated with a photon. At high energies, such processes provide a probe of the QCD dynamics as it is dependent on the nuclear gluon distribution, and could be usefull in constraining the behavior of the nuclear gluon distribution in proton-nucleus and nucleus-nucleus collisions. Here we study the influence of the shadowing effect, in the production of J/Ψ+γ at the LHC and estimate the pT dependence of the nuclear modification factors. The theoretical framework considered for J/Ψ+γ production is the non-relativistic QCD (NRQCD) factorization formalism.