CLS 2+1 flavor simulations at physical light- and strange-quark masses

TL;DR

This paper discusses the generation of a 2+1 flavor lattice QCD ensemble at physical quark masses, detailing the simulation setup, challenges, and initial results to improve precision in fundamental physics calculations.

Contribution

It presents the first steps in generating a physical 2+1 flavor lattice ensemble with multiple lattice spacings and discusses the thermalization strategy and initial observable results.

Findings

Ensemble generated at physical light and strange quark masses.

Simulation covers five lattice spacings from 0.039 to 0.086 fm.

Initial results for simple observables are presented.

Abstract

We report recent efforts by CLS to generate an ensemble with physical light- and strange-quark masses in a lattice volume of 192x96^3 at $\beta=3.55$ corresponding to a lattice spacing of 0.064 fm. This ensemble is being generated as part of the CLS 2+1 flavor effort with improved Wilson fermions. Our simulations currently cover 5 lattice spacings ranging from 0.039 fm to 0.086 fm at various pion masses along chiral trajectories with either the sum of the quark masses kept fixed, or with the strange-quark mass at the physical value. The current status of simulations is briefly reviewed, including a short discussion of measured autocorrelation times and of the main features of the simulations. We then proceed to discuss the thermalization strategy employed for the generation of the physical quark-mass ensemble and present first results for some simple observables. Challenges encountered in the simulation are highlighted.