Constraints for proton structure fluctuations from exclusive scattering

TL;DR

This paper uses the Color Glass Condensate framework to analyze exclusive vector meson production in deep inelastic scattering, revealing that significant gluonic density fluctuations are necessary to match experimental data.

Contribution

It provides the first quantitative constraints on the proton's density profile and fluctuations using both coherent and incoherent scattering data.

Findings

Gluonic density of the proton exhibits large geometric fluctuations.

The model successfully describes the measured incoherent cross section.

Constraints on the proton's average density profile are established.

Abstract

We constrain the average density profile of the proton and the amount of event-by-event fluctuations by simultaneously calculating the coherent and incoherent exclusive diffractive vector meson production cross section in deep inelastic scattering. Working within the Color Glass Condensate picture, we find that the gluonic density of the proton must have large geometric fluctuations in order to describe the experimentally measured large incoherent cross section.