Approach to the time development of parton fragmentation

TL;DR

This paper develops a Monte Carlo-based approach to model the time evolution of parton fragmentation in a quark-gluon plasma, emphasizing the importance of temporal dynamics in understanding medium effects.

Contribution

It introduces a novel Monte Carlo algorithm approximating DGLAP evolution with a focus on the time development of partonic cascades in a non-static medium.

Findings

Implemented algorithms for parton cascade simulation.

Analyzed temporal evolution of parton multiplicities and virtualities.

Provided insights into when parton splittings occur during fragmentation.

Abstract

It is the central goal of our studies to describe parton fragmentation in the hot and dense medium of a quark gluon plasma (QGP). Under the assumption that the medium is not static and homogeneous, knowledge about the temporal evolution of the processes involved can be of essential importance. Therefore, parton fragmentation has been studied with a Monte-Carlo algorithm that approximates the DGLAP-evolution of fragmentation functions via a set of parton cascades. The presented work consists mainly of implementations of this kind of algorithm and the application of a simple approximation, which gives the time development of partonic cascades. As approximations to the parton-splitting processes of gluons and massless quarks in the vacuum two different schemes with the same leading-log contributions are investigated. Furthermore, the temporal evolutions of quantities related to partonic cascades have been examined: To our understanding, especially variables (like, e.g.: parton multiplicities or virtualities) that give insight, when parton splittings take place, are of great interest, as they allow identifying the parts of the fragmentation process that will be most affected by medium interactions.