2+1 Flavor Lattice QCD with Luescher's Domain-Decomposed HMC Algorithm

TL;DR

This study explores the application of Luescher's domain-decomposed HMC algorithm to 2+1 flavor lattice QCD, assessing its efficiency and potential to reach lighter quark masses near physical values.

Contribution

It provides a preliminary evaluation of Luescher's domain-decomposed HMC algorithm's effectiveness for simulating lighter quark masses in 2+1 flavor lattice QCD.

Findings

LDDHMC can reach lighter quark masses than conventional HMC.

The algorithm shows improved efficiency over traditional methods.

Parameter optimization is crucial for large-scale production runs.

Abstract

We report on a study of 2+1 flavor lattice QCD with the $O(a)$-improved Wilson quarks on a $16^3\times 32$ lattice at the lattice spacing $1/a\approx 2$GeV employing Luescher's domain-decomposed HMC(LDDHMC) algorithm. This is dedicated to a preliminary study for the PACS-CS project which plans to complete the Wilson-clover $N_f=2+1$ program lowering the up-down quark masses close to the physical values as much as possible. We focus on three issues: (i) how light quark masses we can reach with LDDHMC, (ii) efficiency of the algorithm compared with the conventional HMC, (iii) parameter choice for the production runs on PACS-CS.