Topological susceptibility and the sampling of field space in $N_f=2$ lattice QCD simulations

TL;DR

This paper measures the topological susceptibility in two-flavor lattice QCD, addressing autocorrelation and cutoff effects, and finds agreement with chiral perturbation theory within statistical accuracy.

Contribution

It provides the first detailed lattice QCD measurement of topological susceptibility for two flavors, analyzing autocorrelations and cutoff effects.

Findings

Autocorrelations are significant in the observable.

Cutoff effects are sizable and must be carefully managed.

Results agree with leading order chiral perturbation theory.

Abstract

We present a measurement of the topological susceptibility in two flavor QCD. In this observable, large autocorrelations are present and also sizable cutoff effects have to be faced in the continuum extrapolation. Within the statistical accuracy of the computation, the result agrees with the expectation from leading order chiral perturbation theory.