NNLO Corrections to the Polarized Drell-Yan Coefficient Function

Abstract

We present the full next-to-next-to-leading order (NNLO) corrections to the coefficient function for the polarized cross section $d\Delta \sigma /dQ$ of the Drell-Yan process. We study the effect of these corrections on the process $p+p\to l^{+}{l}^{-}+‘X^{\prime }$ at an C.M. energy $\sqrt{S}=200GeV$. All QCD partonic subprocesses have been included provided the lepton pair is created by a virtual photon, which is a valid approximation for a lepton pair invariant mass $Q<50GeV$. For this reaction the dominant subprocess is given by $q+\bar{q}\to {\gamma }^{\ast }+‘X^{\prime }$ and its higher order corrections so that it provides us with an excellent tool to measure the polarized sea-quark densities.

5 pages, 5 figures, 7th DESY Workshop on Elementary Particle Theory, Loops and Legs in Quantum Field Theory, Zinnowitz, Germany, April 25-30, 2004