The pT spectrum in heavy-flavour photoproduction

Abstract

We consider the transverse-momentum distribution of heavy flavours in photon-hadron collisions. We present a formalism in which large transverse-momentum logarithms are resummed to the next-to-leading level, and mass effects are included exactly up to order αemαS2, so as to retain predictivity at both small and large transverse momenta. Phenomenological applications relevant to charm photoproduction at HERA are given.