Gluon saturation in proton and its contribution to single inclusive soft gluon production in high energy proton-nucleus collisions

TL;DR

This paper provides a comprehensive analytical calculation of single inclusive soft gluon production in high energy proton-nucleus collisions, incorporating gluon saturation effects from the Color Glass Condensate framework.

Contribution

It presents the complete analytical result for gluon saturation corrections in pA collisions using classical Yang-Mills equations and LSZ reduction, advancing beyond partial previous results.

Findings

Complete analytical expression for gluon saturation correction.

Inclusion of both initial and final state interactions.

Advancement over previous partial results.

Abstract

The leading order single inclusive soft gluon production in high energy proton-nucleus (pA) collisions has been studied by various approaches for more than two decades. The first correction due to the gluon saturation in proton was analytically attempted recently through a diagrammatic approach in which only partial results were obtained. An important feature of the first saturation correction is that it includes both initial state and final state interactions. In this paper, we present the complete result derived from the Color Glass Condensate framework. Our approach is to analytically solve the classical Yang-Mills equations in the dilute-dense regime and then use the Lehmann-Symanzik-Zimmermann (LSZ) reduction formula to obtain gluon production from classical gluon fields.