Higgs boson production at the LHC: transverse-momentum resummation and rapidity dependence
Abstract
We consider Higgs boson production by gluon fusion in hadron collisions. We study the doubly-differential transverse-momentum (qT) and rapidity (y) distribution of the Higgs boson in perturbative QCD. In the region of small qT (qT << MH, MH being the mass of the Higgs boson), we include the effect of logarithmically-enhanced contributions due to multiparton radiation to all perturbative orders. We use the impact parameter and double Mellin moments to implement and factorize the multiparton kinematics constraint of transverse- and longitudinal-momentum conservation. The logarithmic terms are then systematically resummed in exponential form. At small qT, we perform the all-order resummation of large logarithms up to next-to-next-to-leading logarithmic accuracy, while at large qT (qT ~ MH), we apply a matching procedure that recovers the fixed-order perturbation theory up to next-to-leading order. We present quantitative results for the differential cross section in qT and y at the LHC, and we comment on the comparison with the qT cross section integrated over y.