Parton Saturation at Small x and in Large Nuclei

TL;DR

This paper investigates the behavior of quark and gluon distributions in high-energy hadrons and nuclei within the saturation regime, using one-loop calculations and the Weizsacker-Williams wavefunction to understand small x physics.

Contribution

It provides explicit one-loop calculations of parton distributions in the saturation regime and validates the use of the Weizsacker-Williams wavefunction for gluon distribution physics.

Findings

Explicit one-loop calculations of parton distributions in saturation regime

Validation of Weizsacker-Williams wavefunction for gluon distributions

Insights into small x physics in high-energy nuclei

Abstract

Quark and gluon distributions in the light-cone wavefunction of a high energy hadron or nucleus are calculated in the saturation regime. One loop calculations are performed explicitly using the equivalence between the parton distribution in the light-cone wavefunction and the production distribution of that parton in a current-nucleon (nucleus) scattering. We argue that, except for some overall numerical factors, the Weizsacker- Williams wavefunction correctly gives the physics of the gluon distribution in a light-cone wavefunction.