Transverse Single Spin Asymmetries and Charmonium Production

Abstract

We estimate transverse spin single spin asymmetry(TSSA) in the process $e+p^{\uparrow }\to J/\psi +X$ using color evaporation model of charmonium production. We take into account transverse momentum dependent(TMD) evolution of Sivers function and parton distribution function and show that the there is a reduction in the asymmetry as compared to our earlier estimates wherein the $Q^2$ - evolution was implemented only through DGLAP evolution of unpolarized gluon densities.

Comments: Proceedings of Light Cone 2012, New Delhi, India