2+1 flavor lattice QCD simulation with $O(a)$-improved Wilson quarks

TL;DR

This paper reports on detailed lattice QCD simulations with 2+1 flavors using improved Wilson quarks, achieving near-physical quark masses and comparing the results with experimental data.

Contribution

It introduces an improved simulation setup with the Luscher's domain-decomposed HMC algorithm to approach physical quark masses in lattice QCD.

Findings

Pseudoscalar meson masses range from 702MeV to 156MeV.

Light hadron spectrum at the physical point agrees with experimental values.

Provides quark masses and decay constants consistent with known results.

Abstract

We present simulation details and results for the light hadron spectrum in N f = 2 + 1 lattice QCD with the nonperturbatively O(a)-improved Wilson quark action and the Iwasaki gauge action. Simulations are carried out at a lattice spacing of 0.09 fm on a (2.9fm)^3 box using the PACS-CS computer. We employ the Luscher's domain-decomposed HMC algorithm with several improvements to reduce the degenerate up-down quark mass toward the physical value. So far the resulting pseudoscalar meson mass is ranging from 702MeV down to 156MeV. We discuss on the stability and the efficiency of the algorithm. The light harden spectrum extrapolated at the physical point is compared with the experimental values. We also present the values of the quark masses and the pseudoscalar meson decay constants.