Probing short-range nucleon-nucleon interactions with an Electron-Ion Collider

TL;DR

This paper proposes a method to study short-range nucleon-nucleon interactions using exclusive vector meson production at a future Electron-Ion Collider, providing new insights into nuclear forces at the quark-gluon level.

Contribution

It introduces a novel gluon Transition Generalized Parton Distribution (T-GPD) framework to probe short-range nuclear interactions in high-energy scattering.

Findings

Estimates for deuteron disintegration rates at EIC energies.

Potential to access nucleon-nucleon center-of-mass energies around 12 GeV.

Demonstrates EIC's capability to explore short-range nuclear dynamics.

Abstract

We derive the cross-section for exclusive vector meson production in high energy deeply inelastic scattering off a deuteron target that disintegrates into a proton and a neutron carrying large relative momentum in the final state. This cross-section can be expressed in terms of a novel gluon Transition Generalized Parton Distribution (T-GPD); the hard scale in the final state makes the T-GPD sensitive to the short distance nucleon-nucleon interaction. We perform a toy model computation of this process in a perturbative framework and discuss the time scales that allow the separation of initial and final state dynamics in the T-GPD. We outline the more general computation based on the factorization suggested by the toy computation: in particular, we discuss the relative role of "point-like" and "geometric" Fock configurations that control the parton dynamics of short range nucleon-nucleon scattering. With the aid of exclusive $J/\Psi$ production data at HERA, as well as elastic nucleon-nucleon cross-sections, we estimate rates for exclusive deuteron photo-disintegration at a future Electron-Ion Collider (EIC). Our results, obtained using conservative estimates of EIC integrated luminosities, suggest that center-of-mass energies $s_{NN}\sim 12$ GeV$^2$ of the neutron-proton subsystem can be accessed. We argue that the high energies of the EIC can address outstanding dynamical questions regarding the short-range quark-gluon structure of nuclear forces by providing clean gluon probes of such "knockout" exclusive reactions in light and heavy nuclei.