Sivers Effect and Transverse Single Spin Asymmetry in $e+p^\uparrow \to e+J/\psi+X$

TL;DR

This paper explores using J/ψ electroproduction to probe the gluon Sivers function by measuring single spin asymmetry in polarized proton-electron collisions, estimating asymmetries up to 25% across various experimental energies.

Contribution

It introduces a novel method to investigate the gluon Sivers function through J/ψ production in polarized electron-proton collisions, with quantitative SSA estimates.

Findings

SSA up to 25% at certain model parameters

Feasible measurements at JLab, HERMES, COMPASS, and eRHIC energies

Supports using J/ψ electroproduction as a gluon Sivers function probe

Abstract

We discuss the possibility of using electroproduction of $J/\psi $ as a probe of gluon Sivers function by measuring single spin asymmetry (SSA) in experiments with transversely polarized protons and electron beams. We estimate SSA for JLab, HERMES, COMPASS and eRHIC energies using the color evaporation model of charmonium production and find asymmetry up to 25% for certain choices of model parameters which have been used earlier for estimating SSA in the SIDIS and Drell-Yan processes.