Drell-Yan lepton pair production at high energies in the parton Reggeization approach

Abstract

According to extensive theoretical studies of the high-energy limit of QCD, inelastic interactions are dominated by the multi-Regge final states. The appropriate gauge-invariant objects, which simultaneously incorporate the transverse momentum degrees of freedom, are Reggeized gluons, quarks and antiquarks. In the present communication we extend parton Reggeization approach to Drell-Yan production of massive lepton pairs. The basic ingredient is a process of Reggeized quark-antiquark annihilation, $\mathcal{Q}\overline{\mathcal{Q}}\ensuremath{\rightarrow}{\ensuremath{\gamma}}^{\ensuremath{\star}}\ensuremath{\rightarrow}{l}^{+}{l}^{\ensuremath{-}}$, which is described by the Reggeon-Reggeon-photon effective vertex ${\ensuremath{\Gamma}}_{\mathcal{Q}\overline{\mathcal{Q}}}^{\ensuremath{\gamma}}$. We calculate transverse-momentum and invariant-mass distributions of Drell-Yan lepton pairs measured at the CERN SPS, FNAL Tevatron and CERN LHC in the different ranges of energy and rapidity. We focus on angular distributions of Drell-Yan leptons in different kinematical ranges. The obtained results are compared with the existing data and a good agreement is found. The predictions for future experiments for Drell-Yan lepton pair production at the CERN LHC have been made.