Baryon stopping as a relativistic Markov process in phase space

TL;DR

This paper develops a relativistic Markov process model for baryon stopping in heavy-ion collisions, integrating quantum chromodynamics with a diffusion approach to match experimental rapidity distribution data.

Contribution

It introduces a fully time-dependent, QCD-consistent relativistic diffusion model for baryon stopping using a Markov process in phase space.

Findings

Model reproduces net-proton rapidity distributions from SPS and RHIC.

Provides a new theoretical framework linking QCD with stochastic diffusion.

Numerical solutions align well with experimental data.

Abstract

We reconsider baryon stopping in relativistic heavy-ion collisions in a nonequilibrium-statistical framework. The approach combines earlier formulations based on quantum chromodynamics with a relativistic diffusion model through a suitably derived fluctuation-dissipation relation, thus allowing for a fully time-dependent theory that is consistent with QCD. We use an existing framework for relativistic stochastic processes in spacetime that are Markovian in phase space, and adapt it to derive a Fokker-Planck equation in rapidity space, which is solved numerically. The time evolution of the net-proton distribution function in rapidity space agrees with stopping data from the CERN Super Proton Synchrotron and the BNL Relativistic Heavy Ion Collider.