Relativistic Nucleus-Nucleus Collisions: Zone of Reactions and Space-Time Structure of a Fireball

TL;DR

This paper investigates the space-time structure of a fireball created in relativistic nucleus-nucleus collisions by analyzing reaction zones and freeze-out hypersurfaces using the UrQMD transport model.

Contribution

It introduces the concept of a reaction zone as a tool to study the space-time evolution of the collision system and relates it to freeze-out hypersurfaces.

Findings

Reaction zones can be identified and analyzed in relativistic nuclear collisions.

The study links reaction zones to chemical and kinetic freeze-out hypersurfaces.

Time-dependent reaction rates provide insights into the evolution of the fireball.

Abstract

A zone of reactions is determined and then exploited as a tool in studying the space-time structure of an interacting system formed in a collision of relativistic nuclei. The time dependence of the reaction rates integrated over spatial coordinates is also considered. Evaluations are made with the help of the microscopic transport model UrQMD. The relation of the boundaries of different zones of reactions and the hypersurfaces of sharp chemical and kinetic freeze-outs is discussed.