VECTOR MESON-HADRON COLLISIONS: LARGE INVARIANT MASS AND TRANSVERSE MOMENTUM LEPTON PAIR PRODUCTION

Abstract

In the framework of factorized perturbative QCD, higher twist mesonic binding effects in lepton pair production in vector meson-hadron collisions are investigated. A general expression for the higher twist contributions is derived. As an example, these contributions are calculated in the case of the ρ meson-proton collision and comparisons are made to leading twist ones. It is shown that the higher twist contributions induced by a transversely polarized ρT meson are large for all values of the dilepton transverse momentum pT (2 GeV≤pT≤6 GeV). In the kinematic regimes τ=Q2/S→1 or xF→1, the higher twist corrections induced by both ρT and ρL exceed considerably the leading ones. The Drell-Yan processes with dilepton rapidity y>0 are especially preferable for the observation of these effects.