Determining the strange quark mass for 2-flavour QCD

Abstract

Using the O ( a ) Symanzik improved action an estimate is given for the strange quark mass for unquenched ( n f = 2 ) QCD. The determination is via the axial Ward identity (AWI) and includes a non-perturbative evaluation of the renormalisation constant. Numerical results have been obtained at several lattice spacings, enabling the continuum limit to be taken. Our results indicate a value for the strange quark mass (in the M S ¯ -scheme at a scale of 2 GeV) in the range 100 – 130 MeV. A comparison is also made with other recent lattice determinations of the strange quark mass using dynamical sea quarks.