Improved Wilson QCD simulations with light quark masses

TL;DR

This paper reports on advanced Wilson QCD simulations with light quark masses, providing new insights into meson masses, chiral logarithms, topological susceptibility, and algorithm performance at near-physical quark masses.

Contribution

It introduces improved simulation results with light quark masses, highlighting new data on meson masses, chiral effects, and topological susceptibility, along with performance analysis of the HMC algorithm.

Findings

Mass of the singlet pseudoscalar meson measured

Evidence of chiral logarithms in pion decay constant

Suppression of topological susceptibility confirmed at light quark masses

Abstract

We present results from simulations using 2 flavours of O(a)-improved Wilson quarks whose masses are about 1/3 of the physical strange quark mass. We present new data on the mass of the singlet pseudoscalar meson and evidence of the onset of chiral logarithms in the pion decay constant. The previously observed suppression of the topological susceptibility at lighter quark masses is confirmed. We report on the performance of the hybrid Monte Carlo algorithm at light quark masses.