Transverse spin asymmetries for W-production in proton-proton collisions

TL;DR

This paper investigates transverse spin asymmetries in W-boson production during proton-proton collisions, using twist-3 factorization to connect observables with quark-gluon correlations, providing insights relevant for RHIC experiments.

Contribution

It introduces a twist-3 collinear factorization approach to analyze transverse spin asymmetries in W-production, linking them to quark-gluon-quark correlations and proposing experimental tests.

Findings

Numerical estimates for RHIC kinematics are provided.

Parity-even transverse single spin correlation can test QCD spin asymmetry models.

The study connects asymmetries to transverse momentum dependent distributions.

Abstract

We study parity-even and parity-odd polarization observables for the process $p \, p \to l^{\pm} \, X$, where the lepton comes from the decay of a $W$-boson. By using the collinear twist-3 factorization approach, we consider the case when one proton is transversely polarized, while the other is either unpolarized or longitudinally polarized. These observables give access to two particular quark-gluon-quark correlation functions, which have a direct relation to transverse momentum dependent parton distributions. We present numerical estimates for RHIC kinematics. Measuring, for instance, the parity-even transverse single spin correlation would provide a crucial test of our current understanding of single spin asymmetries in the framework of QCD.