Perturbative T -odd asymmetries in the Drell-Yan process revisited

Abstract

We calculate the perturbative T-odd contributions to the lepton angular distribution in the Drell-Yan process. Using collinear factorization, we work at the first order in QCD perturbation theory where these contributions appear, O(αs2), and address both W± and γ/Z0 boson exchange. A major focus of our calculation is on the regime where the boson’s transverse momentum QT is much smaller than its mass Q. We carefully expand our results up to next-to-next-to-leading power in QT/Q. Our calculation provides a benchmark for studies of T-odd contributions that employ transverse-momentum dependent parton distribution functions. In the neutral-current case we compare our results for the T-odd structure functions to available ATLAS data. Published by the American Physical Society 2024