Non-perturbatively renormalised light quark masses from a lattice simulation with N_f=2

TL;DR

This paper reports on non-perturbatively renormalized light quark masses from lattice QCD simulations with two dynamical flavors, providing results that are more accurate than perturbative methods and consistent with quenched approximations.

Contribution

The study introduces a non-perturbative RI-MOM renormalization approach for light quark masses in lattice QCD with N_f=2, improving accuracy over perturbative methods.

Findings

Quark masses are about 15% larger with non-perturbative renormalization.

Results are consistent with previous quenched simulations.

Provides specific values for up/down and strange quark masses at 2 GeV.

Abstract

We present results for the light quark masses obtained from a lattice QCD simulation with N_f=2 degenerate Wilson dynamical quark flavours. The sea quark masses of our lattice, of spacing a ~ 0.06 fm, are relatively heavy, i.e., they cover the range corresponding to 0.60 <~ M_P/M_V <~ 0.75. After implementing the non-perturbative RI-MOM method to renormalise quark masses, we obtain m_{ud}^{MS}(2 GeV)=4.3 +- 0.4^{+1.1}_{-0} MeV, and m_s^{MS}(2 GeV)=101 +- 8^{+25}_{-0} MeV, which are about 15% larger than they would be if renormalised perturbatively. In addition, we show that the above results are compatible with those obtained in a quenched simulation with a similar lattice.