Exploring origin of small x saturation in collinear approach

TL;DR

This paper proposes a modified collinear evolution approach to better understand small x saturation, suggesting that parton diffusion at high densities leads to a natural saturation scale.

Contribution

It introduces a modification to collinear evolution equations to incorporate saturation effects and provides theoretical arguments for the emergence of a saturation scale.

Findings

Modified evolution equations improve small x behavior

Parton diffusion leads to a natural saturation scale

The approach offers theoretical insights into saturation regime

Abstract

A modification of the collinear evolution equations as an appropriate approach to improve the behavior of parton distribution functions in the region of small longitudinal momentum fractions, and to find more theoretical arguments to clarify the possible appearence of saturation regime is suggested. It is argued that parton diffusion in the rapidity space at large parton densities along the space-time evolution could result in the emergence of a natural saturation scale on which freezing actually occurs.