# Rapidity distribution of particle multiplicity in DIS at small x

## TL;DR

This paper analytically investigates the rapidity distribution of particles produced in deep inelastic scattering at small x, focusing on different sources like quark-antiquark fragmentation, soft gluon radiation, and gluon fragmentation, and discusses theoretical connections to CCFM equations.

## Contribution

It provides a detailed analytical framework for understanding particle production sources in DIS at small x, linking to CCFM evolution and gluon reggeization.

## Key findings

- Identifies three main sources of particle production in DIS at small x.
- Analyzes the role of gluon reggeization in rapidity distributions.
- Connects particle production mechanisms to CCFM evolution equations.

## Abstract

Analytical study of the rapidity distribution of the final state particles in deep inelastic scattering at small x is presented. We separate and analyse three sources of particle production: fragmentation of the quark-antiquark pair, accompanying coherent soft gluon radiation due to octet color exchange in the t-channel, and fragmentation of gluons that form parton distribution functions. Connection to Catani-Ciafaloni-Fiorani-Marchesini (CCFM) equations and the role of gluon reggezation are also discussed.