The continuum limit of quark number susceptibilities

TL;DR

This paper investigates the continuum limit of quark number susceptibilities in quenched QCD, revealing deviations from ideal gas behavior and comparing results with theoretical models, with implications for heavy-ion collision experiments.

Contribution

It provides the continuum extrapolation of quark number susceptibilities in quenched QCD and compares them with ideal gas and HTL predictions, highlighting their differences.

Findings

Susceptibilities are 20% below ideal gas values.

Deviations decrease with finer lattice spacing.

Susceptibilities correlate with screening masses.

Abstract

We report the continuum limit of quark number susceptibilities in quenched QCD. Deviations from ideal gas behaviour at temperature T increase as the lattice spacing is decreased from T/4 to T/6, but a further decrease seems to have very little effect. The measured susceptibilities are 20% lower than the ideal gas values, and also 10% below the hard thermal loop (HTL) results. The off-diagonal susceptibility is several orders of magnitude smaller than the HTL results. We verify a strong correlation between the lowest screening mass and the susceptibility. We also show that the quark number susceptibilities give a reasonable account of the Wroblewski parameter, which measures the strangeness yield in a heavy-ion collision.