Single-spin physics with weak bosons at RHIC

Abstract

In order to measure spin-dependent parton distributions in production of W ± bosons using the non-hermetic detectors of the Relativistic Heavy Ion Collider, an accurate model for distributions of charged leptons from the W-boson decay is needed. We discuss the predictions for production and decay of the W bosons based on a calculation for resummation of large logarithmic contributions originating from multiple soft gluon radiation. We compare the predictions for the spin-dependent resummed cross sections with the corresponding next-to-leading order results. We show that the lepton-level asymmetries can be reliably predicted by the resummation calculation and directly compared to the experimental data. A program for the numerical analysis of such cross sections in γ ∗ -, W ±-, and Z 0-boson production is also presented.