Lattice determination of light quark masses

Abstract

A fully non-perturbative lattice determination of the up/down and strange quark masses is given for quenched QCD using both, O(a) improved Wilson fermions and ordinary Wilson fermions. For the strange quark mass with O(a) improved fermions we obtain m M S s (µ = 2 GeV) = 105(4) MeV, using the interquark force scale r 0 . Due to quenching problems fits are only possible for quark masses larger than the strange quark mass. If we extrapolate our fits to the up/down quark mass we find for the average mass m M S l (µ = 2 GeV) = 4.4(2) MeV.

Hadron spectrum, quark masses, and decay constants from light overlap fermions on large lattices

“…The four-loop value for ∆ M S S (µ) has been given in [36]. At µ = 2 GeV it is ∆ M S S (2 GeV) = 0.721 (10).…”

Light quark masses from lattice quark propagators at large momenta

“…data to Eq. (25), we obtain A = 0.617 (11), to be compared to A (BPT) = 0.573, as computed in one-loop (boosted) perturbation theory [33] 8 . According to Eq.…”

“…(35) we get the results quoted in Eq. (11). In the calculation of m RGI q and m MS (µ), we have used the physical value of α s (µ), corresponding to α s (M Z ) = 0.118 [38], computed with the appropriate number of active flavors, e.g.…”

“…In the past year, several independent lattice determinations of the light quark masses [9]- [11] have been presented, adopting both non-perturbative renormalization procedures and non-perturbative improvement.…”

Estimating the unquenched strange quark mass from the lattice axial Ward identity

“…(Recent n f = 2 + 1 results [7], have finer lattice spacings.) These authors quote strange quark masses of O(80) MeV, lying 15 − 30% below the corresponding quenched results [9,10].…”