High temperature QCD with three flavors of improved staggered quarks

TL;DR

This paper updates high temperature QCD simulations with three flavors of improved staggered quarks, showing reduced lattice artifacts and providing insights into quark susceptibilities relevant for heavy ion collision experiments.

Contribution

It introduces improved lattice simulations of high temperature QCD with three flavors, including new calculations of quark susceptibilities using the Asqtad action.

Findings

Reduced lattice artifacts with improved quark action

First computations of quark number susceptibilities

Simulations across various lattice sizes and quark masses

Abstract

We present an update of our study of high temperature QCD with three flavors of quarks, using a Symanzik improved gauge action and the Asqtad staggered quark action. Simulations are being carried out on lattices with Nt=4, 6 and 8 for the case of three degenerate quarks with masses less than or equal to the strange quark mass, $m_s$, and on lattices with Nt=6 and 8 for degenerate up and down quarks with masses in the range 0.2 m_s \leq m_{u,d} \leq 0.6 m_s, and the strange quark fixed near its physical value. We also report on first computations of quark number susceptibilities with the Asqtad action. These susceptibilities are of interest because they can be related to event-by-event fluctuations in heavy ion collision experiments. Use of the improved quark action leads to a substantial reduction in lattice artifacts. This can be seen already for free fermions and carries over into our results for QCD.