High-precision fBs and heavy quark effective theory from relativistic lattice QCD

McNeile, C., Davies, C.T.H. , Follana, E., Hornbostel, K. and Lepage, G.P. (2012) High-precision fBs and heavy quark effective theory from relativistic lattice QCD. Physical Review D, 85(3), 031503. (doi: 10.1103/PhysRevD.85.031503)

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Publisher's URL: http://dx.doi.org/10.1103/PhysRevD.85.031503

Abstract

We present a new determination of the Bs leptonic decay constant from lattice QCD simulations that use gluon configurations from MILC and a highly improved discretization of the relativistic quark action for both valence quarks. Our result, fBs=0.225(4)  GeV, is almost 3 times more accurate than previous determinations. We analyze the dependence of the decay constant on the heavy quark’s mass and obtain the first empirical evidence for the leading 1/√mh dependence predicted by heavy quark effective theory. As a check, we use our analysis technique to calculate the mBs-mηb/2 mass difference. Our result agrees with experiment to within errors of 11 MeV (better than 2%). We discuss how to extend our analysis to other quantities in Bs and B physics, making 2% precision possible for the first time.

Item Type:Articles
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Follana, Dr Eduardo and McNeile, Dr Craig and Davies, Professor Christine
Authors: McNeile, C., Davies, C.T.H., Follana, E., Hornbostel, K., and Lepage, G.P.
College/School:College of Science and Engineering > School of Physics and Astronomy
Journal Name:Physical Review D
Publisher:American Physical Society
ISSN:1550-7998
ISSN (Online):1550-2368
Published Online:07 February 2012

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