Continuum and lattice meson spectral functions at nonzero momentum and high temperature

TL;DR

This paper investigates discretization effects on high-temperature meson spectral functions at nonzero momentum on the lattice, comparing continuum and lattice results to improve understanding of lattice artifacts.

Contribution

It provides analytical continuum spectral densities and simple lattice expressions for Wilson and staggered fermions, enhancing the analysis of lattice discretization effects at high temperature.

Findings

Analytical continuum spectral densities derived

Lattice spectral functions for Wilson and staggered fermions formulated

Discretization effects characterized and compared

Abstract

We analyse discretization effects in the calculation of high-temperature meson spectral functions at nonzero momentum and fermion mass on the lattice. We do so by comparing continuum and lattice spectral functions in the infinite temperature limit. Complete analytical results for the spectral densities in the continuum are presented, along with simple expressions for spectral functions obtained with Wilson and staggered fermions on anisotropic lattices. We comment on the use of local and point split currents.