We extend our analysis of transverse single spin asymmetry (SSA) in electroproduction of J/ψ to include the effect of the scale evolution of the transverse momentum dependent (TMD) parton distribution functions and gluon Sivers function. We estimate SSA for JLab, HERMES, COMPASS, and eRHIC energies using the color evaporation model of charmonium production, using an analytically obtained approximate solution of TMD evolution equations discussed in the literature. We find that there is a reduction in the asymmetry compared with our predictions for the earlier case considered by us, wherein the Q2 dependence came only from DGLAP evolution of the unpolarized gluon densities and a different parametrization of the TMD Sivers function was used.
@article{arxiv.1304.2584,
title = {Transverse Single Spin Asymmetry in $e+p^\uparrow \to e+J/\psi +X $ and Transverse Momentum Dependent Evolution of the Sivers Function},
author = {Rohini M. Godbole and Anuradha Misra and Asmita Mukherjee and Vaibhav S. Rawoot},
journal= {arXiv preprint arXiv:1304.2584},
year = {2013}
}
Comments
12 pages, 6 figures. arXiv admin note: text overlap with arXiv:1201.1066