# Sivers Asymmetry in Photoproduction of $J/\psi$ and Jet at the EIC

## TL;DR

This paper predicts a sizable Sivers asymmetry in $J/$-jet photoproduction at the future EIC, using the GPM and NRQCD frameworks, to help determine the gluon Sivers function.

## Contribution

It introduces a detailed calculation of the Sivers asymmetry in $J/$-jet production, including color states and TMD evolution effects, for the first time.

## Key findings

- Sizable Sivers asymmetry predicted for EIC conditions.
- Both color singlet and octet states significantly contribute.
- TMD evolution impacts the magnitude of the asymmetry.

## Abstract

We calculate the Sivers asymmetry in the photoproduction of almost back-to-back $J/\psi$-jet pair in the process $ep^\uparrow \to J/\psi+\mathrm{jet}+X$, which will be possible at the future planned electron-ion collider (EIC). We use the framework of generalized parton model (GPM), and NRQCD for calculating the $J/\psi$ production rate. We include contributions from both color singlet and color octate states in the asymmetry. We obtain sizable Sivers asymmetry that can be promising to determine the gluon Sivers function. We also investigate the effect of TMD evolution on the asymmetry.