The twist-3 gluon contribution to Sivers asymmetry in $J/\psi$ production in semi-inclusive deep inelastic scattering

TL;DR

This paper presents the first calculation of the twist-3 gluon contribution to the single transverse-spin asymmetry in $J/eta$ production during semi-inclusive deep inelastic scattering, highlighting its potential to probe gluon distributions.

Contribution

It introduces the first theoretical calculation of the twist-3 gluon contribution to SSA in $J/eta$ production and explores its implications for future electron-ion collider experiments.

Findings

$J/eta$ SSA can directly probe $C$-even twist-3 gluon distributions.

Color-singlet hadronization effects cancel out in SSA, reflecting gluon distributions.

Numerical simulations suggest measurable SSA at future collider kinematics.

Abstract

We carry out the first calculation for the twist-3 gluon contribution to the single transverse-spin asymmetry(SSA) in $J/\psi$ production in semi-inclusive deep inelastic scattering. Our result shows that the $J/\psi$ SSA is an ideal observable to pin down the $C$-even type twist-3 gluon distribution that has a direct relationship with the gluon transverse-momentum-dependent distribution function. We also perform some numerical simulations of the $J/\psi$ SSA for the kinematics accessible at the future electron-ion-collider experiment. For color-singlet contribution, the hadronization effect of $J/\psi$ is completely canceled at the level of the SSA and the spin-dependent structure functions directly reflect the behavior of the $C$-even twist-3 gluon distribution.