Methods for Pseudoscalar Flavour-Singlet Mesons with Staggered Fermions

TL;DR

This paper reports the first 2+1 flavour lattice QCD calculations of pseudoscalar flavour-singlet mesons using improved staggered fermions, highlighting techniques and challenges in error estimation.

Contribution

It introduces novel lattice QCD methods for pseudoscalar flavour-singlet mesons with improved staggered fermions and discusses error estimation challenges.

Findings

Disconnected correlator has a highly non-Gaussian distribution

Reliable error estimates require careful analysis

Techniques for large-scale studies are discussed

Abstract

We present the first 2+1 flavour lattice QCD calculations of pseudoscalar flavour-singlet propagators using improved staggered fermions. We explore the relevant techniques and discuss prospects for the larger scale studies now in progress. The disconnected correlator is shown to have a highly non-Gaussian distribution and reliable estimates of the errors require care.