Incoherent diffractive J/Psi-production in high energy nuclear DIS

TL;DR

This paper calculates the cross sections for incoherent diffractive J/Psi production in high energy nuclear deep inelastic scattering, revealing how saturation effects and impact parameter profiles influence nuclear suppression and the spatial distribution of gluons.

Contribution

It provides the first detailed analysis of incoherent diffractive J/Psi production cross sections, highlighting their dependence on saturation effects and impact parameter fluctuations.

Findings

Cross section scales with A in dilute limit and A^(1/3) in black disc limit.

Nuclear suppression indicates a smoothing of gluon distribution at high energy.

t-dependence sensitive to gluon impact parameter profile and fluctuations.

Abstract

We compute cross sections for incoherent diffractive J/Psi production in lepton-nucleus deep inelastic scattering. The cross section is proportional to A in the dilute limit and to A^(1/3) in the black disc limit, with a large nuclear suppression due to saturation effects. The t-dependence of the cross section, if it can be measured accurately enough, is sensitive to the impact parameter profile of the gluons in the nucleus and their fluctuations, a quantity that determines the initial conditions of a relativistic heavy ion collision. The nuclear suppression in incoherent diffraction shows how the transverse spatial distribution of the gluons in the nucleus gradually becomes smoother at high energy. Since the values of the momentum transfer |t| involved are relatively large, this process should be easier to measure in future nuclear DIS experiments than coherent diffraction.