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Progress Calculating Decay Constants with NRQCD and AsqTad Actions

Matthew Wingate·Christine Davies·Alan Gray·Emel Gulez·G. Peter Lepage·Junko Shigemitsu
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Abstract

We combine a light AsqTad antiquark with a nonrelativistic heavy quark to compute the decay constants of heavy-light pseudoscalar mesons using the ensemble of 3-flavor gauge field configurations generated by the MILC collaboration. Preliminary results for $f_{B_s}$ and $f_{D_s}$ are given and status of the chiral extrapolation to $f_B$ is reported. We also touch upon results of the perturbative calculation which matches matrix elements in the effective theory to the full theory at 1-loop order.

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Matthew Wingate, Christine Davies, Alan Gray, Emel Gulez, G. Peter Lepage, Junko Shigemitsu. 2003-09-15. Progress Calculating Decay Constants with NRQCD and AsqTad Actions. https://arxiv.org/abs/hep-lat/0309092

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