Rapidity gap distribution in diffractive dissociation: predictions for future electron-ion colliders

TL;DR

This paper predicts rapidity gap distributions in diffractive dissociation at future electron-ion colliders using advanced QCD equations, highlighting differences between fixed and running coupling effects and emphasizing the importance of such measurements.

Contribution

It provides the first detailed predictions for rapidity gap distributions incorporating both fixed and running coupling effects using the Kovchegov-Levin equation extensions.

Findings

Fixed and running coupling equations produce different distributions.

Distributions with fixed coupling resemble a recent partonic dissociation model.

Running coupling modifies the distribution shape, aligning qualitatively with the partonic picture.

Abstract

We present predictions for the distribution of rapidity gaps in realistic kinematics of future electron-ion colliders, based on numerical solutions of the original Kovchegov-Levin equation and of its next-to-leading extension taking into account the running of the strong coupling. We find that for the rapidities we have considered, the fixed and the running coupling equations lead to different distributions, rather insensitive to the chosen prescription in the running coupling case. The obtained distributions for the fixed coupling framework exhibit a shape characteristic of a recently proposed partonic picture of diffractive dissociation already at rapidities accessible at future electron-ion colliders. The modification of this shape in the running coupling case can also be understood qualitatively from that picture. Our results confirm the relevance of measurements of such observables for the microscopic understanding of diffractive dissociation in the framework of quantum chromodynamics.