CHIRAL LIMIT AND LIGHT QUARK MASSES IN 2+1 FLAVOR DOMAIN WALL QCD

We present results for meson masses and decay constants measured on 243 x 64 lattices using the domain wall fermion formulation with an extension of the fifth dimension of Ls = 16 for Nf 2 + 1 dynamical quark flavors. The lightest dynamical meson mass in our set-up is around 331MeV. while partially quenched mesons reach masses as low as 250MeV. The applicability of SU(3) x SU(3) and SU(2) x SU(2) (partially quenched) chiral perturbation theory will be compared and we quote values for the low-energy constants from both approaches. We will extract the average light quark and strange quark masses and use a non-perturbative renormalization technique (RI/MOM) to quote their physical values. The pion and kaon decay constants are determined at those values from our chiral fits and their ratio is used to obtain the CKM-matrix element |Vus|. The results presented here include statistical errors only.