Continuum determination of light quark masses from quenched lattice QCD

We compute the strange and the average up/down quark masses in the quenched approximation of lattice QCD, by using the O(a)-improved Wilson action and operators and implementing the non-perturbative renormalization. Our computation is performed at four values of the lattice spacing, from which we could extrapolate to the continuum limit. Our final result for the strange quark mass is msMS(2 GeV)=(106±2±8) MeV. For the average up/down quark mass we obtain mℓMS(2 GeV)=(4.4±0.1±0.4) MeV and the ratio ms/mℓ=(24.3±0.2±0.6).