Effect of sub-nucleon fluctuations on the DVCS process in proton and nuclear targets at the EIC

TL;DR

This paper investigates how sub-nucleon fluctuations affect the DVCS process at the EIC, using a hot-spot model to predict energy dependence and $t$-distributions for proton and nuclear targets.

Contribution

It introduces a hot-spot model to estimate the impact of sub-nucleon fluctuations on DVCS cross-sections and their energy and $t$-distribution behaviors.

Findings

Incoherent cross-section shows a turnover in energy dependence due to sub-nucleon fluctuations.

The ratio of coherent to incoherent cross-sections increases with energy, atomic number, and decreasing $Q^2$.

Predicted a maximum in the $t$-distribution of nuclear incoherent cross-section depending on atomic number and $Q^2$.

Abstract

The impact of the sub - nucleon fluctuations on the Deeply Virtual Compton Scattering (DVCS) process at the Electron - Ion Collider (EIC) is investigated considering proton and nuclear targets. Assuming the hot - spot model, we estimate the energy dependence of the coherent and incoherent cross - sections for different values of the photon virtuality and atomic number. Predictions for the $t$ - distributions are also presented. We demonstrate that the sub - nucleon fluctuations in the proton, as described by the hot - spot model, implies a turn - over in the energy dependence of the incoherent cross - section, with the position of the maximum being dependent of the photon virtuality. Our results indicate that the ratio between the coherent and incoherent cross - sections increases with energy, atomic numbers and for smaller values of $Q^2$. Moreover, we predict a maximum in the $t$ - distribution of the nuclear incoherent cross - section at a fixed center - of - mass energy, which is dependent on the atomic number and $Q^2$.