We present the results of a partially quenched lattice QCD calculation of light quark masses with Nf=2 degenerate dynamical flavors. Numerical simulations are carried out using the plaquette gauge action and the Wilson quark action at β=5.8 (a^−1≃3.2 GeV). The spatial extension of the 243×48 lattice is about 1.5 fm. Configurations have been generated at four values of the sea quark masses, for which the ratio of pseudoscalar over vector meson masses is in the range MP/MV≃0.60÷0.75. An important feature of the present study is the use of non-perturbative renormalization, performed with the RI-MOM method. The effects of dynamical sea quarks in the determination of light quark masses have been investigated by performing a quenched calculation on a similar lattice. Our results for the average up-down and strange quark masses are mud(MS,2 GeV)=4.3(4)(+1.1−0.4) MeV and ms(MS,2 GeV)=101(8)(+25−9) MeV. These values are larger than those obtained by evaluating the quark mass renormalization constants with one-loop (boosted) perturbation theory. Our results for the light quark masses are compatible with those obtained in the quenched simulation. No significant sea quark effects are seen, at the values of sea quark masses used in the present study.
Becirevic, D., Blossier, B., Boucaud, P.h., Gimenez, V., Lubicz, V., Mescia, F., et al. (2006). Non-perturbatively renormalized light quark masses with two dynamical fermions. In Lattice 2005: Proceedings of the 23rd International Symposium on Lattice Field Theory (pp.079).
Non-perturbatively renormalized light quark masses with two dynamical fermions
LUBICZ, Vittorio;TARANTINO, CECILIA
2006-01-01
Abstract
We present the results of a partially quenched lattice QCD calculation of light quark masses with Nf=2 degenerate dynamical flavors. Numerical simulations are carried out using the plaquette gauge action and the Wilson quark action at β=5.8 (a^−1≃3.2 GeV). The spatial extension of the 243×48 lattice is about 1.5 fm. Configurations have been generated at four values of the sea quark masses, for which the ratio of pseudoscalar over vector meson masses is in the range MP/MV≃0.60÷0.75. An important feature of the present study is the use of non-perturbative renormalization, performed with the RI-MOM method. The effects of dynamical sea quarks in the determination of light quark masses have been investigated by performing a quenched calculation on a similar lattice. Our results for the average up-down and strange quark masses are mud(MS,2 GeV)=4.3(4)(+1.1−0.4) MeV and ms(MS,2 GeV)=101(8)(+25−9) MeV. These values are larger than those obtained by evaluating the quark mass renormalization constants with one-loop (boosted) perturbation theory. Our results for the light quark masses are compatible with those obtained in the quenched simulation. No significant sea quark effects are seen, at the values of sea quark masses used in the present study.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
