Coherent and incoherent diffractive hadron production in pA collisions and gluon saturation

TL;DR

This paper investigates how coherent and incoherent diffractive hadron production in high energy pA collisions can serve as probes for gluon saturation effects in QCD, highlighting their energy, rapidity, and atomic number dependencies.

Contribution

It introduces a new observable, the diffractive nuclear modification factor, to quantify nuclear effects and explores signatures of gluon saturation at RHIC, LHC, and EIC.

Findings

Coherent diffractive gluon production is highly sensitive to energy, rapidity, and atomic number.

Incoherent diffractive gluon production probes fluctuations in the color glass condensate.

A new observable, the diffractive nuclear modification factor, is proposed to measure nuclear effects.

Abstract

We study coherent and incoherent diffractive hadron production in high energy quarkonium--heavy nucleus collisions as a probe of the gluon saturation regime of QCD. Taking this process as a model for pA collisions, we argue that the coherent diffractive gluon production, in which the target nucleus states intact, exhibits a remarkable sensitivity to the energy, rapidity and atomic number dependence. The incoherent diffractive gluon production is less sensitive to the details of the low-x dynamics but can serve as a probe of fluctuations in the color glass condensate. As a quantitative measure of the nuclear effects on diffractive hadron production we introduce a new observable -- the diffractive nuclear modification factor. We discuss possible signatures of gluon saturation in diffractive gluon production at RHIC, LHC and EIC.