Mass of the b quark from lattice NRQCD and lattice perturbation theory

We present a determination of the b-quark mass accurate through O(alpha(2)(s)) in perturbation theory and including partial contributions at O(alpha(3)(s)). Nonperturbative input comes from the calculation of the Upsilon and B-s energies in lattice QCD, including the effect of u, d and s sea quarks. We use an improved NRQCD action for the b quark. This is combined with the heavy quark energy shift in NRQCD determined using a mixed approach of high-beta simulation and automated lattice perturbation theory. Comparison with experiment enables the quark mass to be extracted: in the (MS) over bar scheme we find (m) over bar (b)((m) over bar (b)) = 4.166(43) GeV. DOI: 10.1103/PhysRevD.87.07401