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Aspects of determining fBs: scaling and power-law divergences

S. Collins·C. T. H. Davies·J. Hein·J. Shigemitsu·C. Morningstar·A. Ali Khan
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Abstract

We present preliminary results for the decay constant of the Bs meson, fBs, at three values of beta=5.7, 6.0 and 6.2 using NRQCD and clover fermions for the heavy and light quarks respectively. As a consistency check the decay constant has also been extracted from the axial-vector current at finite momentum. In addition, we discuss the cancellation of O(alpha/(aM0)) terms and the remaining uncertainty in fBs from higher order divergences.

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S. Collins, C. T. H. Davies, J. Hein, J. Shigemitsu, C. Morningstar, A. Ali Khan. 1999-08-06. Aspects of determining fBs: scaling and power-law divergences. https://arxiv.org/abs/hep-lat/9908007

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