Soft gluons and the normalization of the Drell-Yan cross section

We analyze the sensitivity of the inclusive Drell-Yan cross section to soft gluons, using a previously developed summation procedure which includes nonleading logaritmic effects. By varying an infrared cutoff in gluon energies, we study the importance of soft, but still perturbative, gluons to the normalization of the cross section or, equivalently, the “K-factor.” The results are strongly dependent on the kinematic range being considered, as well as on the parton distributions of the incoming hadrons.