PaperPanorama

arXiv:2509.04431·v2·Nuclear Theory

Extended applicability domain of viscous anisotropic hydrodynamics in (2+1)-D Bjorken flow with transverse expansion

Yiyang Peng🇨🇳 · Victor E. Ambrus🇷🇴 · Clemens Werthmann🇧🇪 · Sören Schlichting🇩🇪 · Ulrich Heinz🇺🇸 · Huichao Song🇨🇳

Abstract

We perform (2+1)-D simulations of viscous anisotropic hydrodynamics (VAH) under boost-invariant and conformal conditions. Comparing both VAH and traditional viscous hydrodynamics with kinetic theory in the relaxation-time approximation as the underlying microscopic theory, we show that VAH provides a superior description of the evolution across a wide range of opacity, effectively extending the applicability of hydrodynamic modeling. Our results demonstrate VAH's potential for describing collective flow in small systems where traditional hydrodynamics faces challenges.

Comments: 11 pages pages, 4 figures