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arXiv · 1501.01991

Leptonic B- and D-meson decay constants with 2+1 flavors of asqtad fermions

Andreas S. Kronfeld·Ethan T. Neil·James N. Simone·Ruth S. Van de Water
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Abstract

We present the status of our updated D- and B-meson decay-constant analysis, based on the MILC $N_f = 2+1$ asqtad gauge ensembles. Heavy quarks are incorporated using the Wilson clover action with the Fermilab interpretation. This analysis includes ensembles at five lattice spacings from a $\approx$ 0.045 to 0.15 fm, and light sea-quark masses down to 1/20th of the strange-quark mass. Projected error budgets for ratios of decay constants, in particular between bottom- and charm-meson decay constants, are presented.

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Andreas S. Kronfeld, Ethan T. Neil, James N. Simone, Ruth S. Van de Water. 2015-01-08. Leptonic B- and D-meson decay constants with 2+1 flavors of asqtad fermions. https://arxiv.org/abs/1501.01991

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