Causal Baryon Diffusion and Colored Noise for Heavy Ion Collisions

TL;DR

This paper develops a causal, analytically consistent baryon diffusion model with colored noise, suitable for integration into hydrodynamical simulations of heavy ion collisions, advancing the realism of such models.

Contribution

It introduces a novel baryon diffusion model with causality and analyticity, incorporating colored noise and multiple time constants, enhancing heavy ion collision simulations.

Findings

Model ensures causality and analyticity.

Noise correlation is not a delta function.

Can be integrated into 2nd order viscous hydrodynamics.

Abstract

We construct a model for baryon diffusion which has the desired properties of analyticity and causality. The model also has the desired property that the noise correlation function is not a Dirac delta function in space and time. The model depends on three time constants in addition to the diffusion constant. This description can be incorporated into 2nd order viscous hydrodynamical models of heavy ion collisions.