QCD evolution of the Sivers asymmetry

Authors :: Ivan Vitev
Ahmad Idilbi
Zhong-Bo Kang
Miguel G. Echevarria
(Astro)-Particles Physics
Theoretical Physics
Source :: Physical Review D, 89(7):074013. American Physical Society, Garcia Echevarria, M, Idilbi, A, Kang, Z B & Vitev, I 2014, ' QCD evolution of the Sivers asymmetry ', Physical Review D, vol. 89, no. 7, 074013 . https://doi.org/10.1103/PhysRevD.89.074013
Publication Year :: 2014
Publisher :: American Physical Society (APS), 2014.
Abstract: We study the QCD evolution of the Sivers effect in both semi-inclusive deep inelastic scattering (SIDIS) and Drell-Yan production (DY). We pay close attention to the non-perturbative spin-independent Sudakov factor in the evolution formalism and find a universal form which can describe reasonably well the experimental data on the transverse momentum distributions in SIDIS, DY lepton pair and $W/Z$ production. With this Sudakov factor at hand, we perform a global fitting of all the experimental data on the Sivers asymmetry in SIDIS from HERMES, COMPASS and Jefferson Lab. We then make predictions for the Sivers asymmetry in DY lepton pair and $W$ production that can be compared to the future experimental measurements to test the sign change of the Sivers functions between SIDIS and DY processes and constrain the sea quark Sivers functions.<br />Comment: 17 pages, 13 figures, published version in PRD