Quark masses and low-energy constants in the continuum from the tadpole-improved clover ensembles

We present the light -flavor quark masses and low -energy constants using the 2 + 1 flavor full-QCD ensembles with stout smeared -clover fermion action and Symanzik gauge action. Both the fermion and gauge actions are tadpole improved self -consistently. The simulations are performed on 11 ensembles at three lattice spacings a is an element of [0.05, 0.11] fm, four spatial sizes L is an element of [2.5, 5.1] fm, seven pion masses m pi is an element of [135, 350] MeV, and several values of the strange quark mass. The quark mass is defined through the partially conserved axial current relation and renormalized to MS(2 GeV) through the intermediate regularization independent momentum subtraction scheme. The systematic uncertainty of using the symmetric momentum subtraction scheme is also included. Eventually, we predict mu = 2.45(22)(20) MeV, md = 4.74(11)(09) MeV, and ms = 98.8(2.9)(4.7) MeV with the systematic uncertainties from lattice spacing determination, continuum extrapolation and renormalization constant included. We also obtain the chiral condensate sigma 1/3 = 268.6(3.6)(0.7) MeV and the pion decay constant F = 86.6(7)(1.4) MeV in the Nf = 2 chiral limit, and the next -to -leading order low -energy constants t degrees 3 = 2.43(54)(05) and t degrees 4 = 4.322(75)(96).