Anisotropic Flow and Viscous Hydrodynamics

TL;DR

This paper develops a gradient expansion formalism for viscous hydrodynamics with consistent phase space distributions, enabling precise calculations of elliptic flow in heavy-ion collisions.

Contribution

It introduces a systematic method to determine viscous corrections to phase space distributions using kinetic theory constraints.

Findings

Viscous corrections to phase space distribution are consistently derived.

Second order viscous hydrodynamics accurately describes elliptic flow.

The formalism improves the precision of hydrodynamic modeling in heavy-ion physics.

Abstract

We report part of our recent work on viscous hydrodynamics with consistent phase space distribution $f(x,\p)$ for freeze out. We develop the gradient expansion formalism based on kinetic theory, and with the constraints from the comparison between hydrodynamics and kinetic theory, viscous corrections to $f(x,\p)$ can be consistently determined order by order. Then with the obtained $f(x,\p)$, second order viscous hydrodynamical calculations are carried out for elliptic flow $v_2$.