Resummation of Hadroproduction Cross-sections at High Energy

We reconsider the high energy resummation of photoproduction, electroproduction and hadroproduction cross-sections, in the light of recent progress in the resummation of perturbative parton evolution to NLO in logarithms of Q and x. We show in particular that the when the coupling runs the dramatic enhancements found at fixed coupling, due to soft singularities in the partonic cross-sections, are substantially reduced, and are in fact largely accounted for by the usual NLO and NNLO perturbative corrections. This leads to a novel explanation of the large K-factors commonly found in perturbative calculations of hadroproduction cross-sections. We give numerical estimates of high energy resummation effects in inclusive B-production, Drell-Yan and vector boson production, along with their rapidity distributions. We find that resummation modifies the B-production cross-section at the LHC by at most 15%, while the uncertainty due to high energy resummation in W-production is around 5%.