Confronting color dipole and intrinsic kT approaches in D-Y dilepton production

we study the drell-yan dilepton production in proton-nucleus collisions at rhic energies. we use two different approaches: the usual intrinsic transverse momentum approach at nlo in the infinitum momentum frame; and the color dipole in the target rest frame. we compare both formalisms at backward rapidities (proton as a target). at forward rapidities, we use earlier results considering the nucleus in a color glass condensate phase. we show qualitative agreement between the two formalisms through the nuclear modification ratio as a function of both rapidity and transverse momentum and that low-mass dileptons are relevant observables to probe nuclear effects.