Lattice-based equation of state with 3D Ising critical point

TL;DR

This paper develops a lattice-based equation of state incorporating the 3D Ising critical point, extending its applicability to higher densities and providing a stable, causal model for hydrodynamics simulations.

Contribution

It introduces a resummation scheme combined with the 3D Ising model to create a family of equations of state valid up to high baryon chemical potential with correct critical behavior.

Findings

Extended lattice results to μ_B/T=3.5 using resummation.

Produced a family of equations of state valid up to μ_B=700 MeV.

Ensured the equations are stable and causal for hydrodynamics.

Abstract

The BEST Collaboration equation of state combining lattice data with the 3D Ising critical point encounters limitations due to the truncated Taylor expansion up to $\frac{\mu_B}{T} \sim 2.5$. This truncation consequently restricts its applicability at high densities. Through a resummation scheme, the lattice results have been extended to $\frac{\mu_B}{T} = 3.5$. In this article, we amalgamate these ideas with the 3D-Ising model, yielding a family of equations of state valid up to $\mu_B=700 \text{MeV}$ with the correct critical behavior. Our equations of state feature tunable parameters, providing a stable and causal framework-a crucial tool for hydrodynamics simulations.