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arXiv · 1302.3739

The mass of the b-quark from lattice NRQCD and lattice perturbation theory

A. J. Lee·C. J. Monahan·R. R. Horgan·C. T. H. Davies·R. J. Dowdall·J. Koponen
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Abstract

We present a determination of the b-quark mass accurate through O(α_s^2) in perturbation theory and including partial contributions at O(α_s^3). 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 bar scheme we find m_b(m_b) = 4.166(43) GeV.

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A. J. Lee, C. J. Monahan, R. R. Horgan, C. T. H. Davies, R. J. Dowdall, J. Koponen. 2013-03-26. The mass of the b-quark from lattice NRQCD and lattice perturbation theory. https://doi.org/10.1103/physrevd.87.074018

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