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arXiv · 2009.08913

Baryon stopping as a relativistic Markov process in phase space

Johannes Hoelck·Georg Wolschin
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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.

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Johannes Hoelck, Georg Wolschin. 2020-09-18. Baryon stopping as a relativistic Markov process in phase space. https://doi.org/10.1103/physrevresearch.2.033409

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