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arXiv · 1212.0301

B-physics from lattice QCD...with a twist

N. Carrasco·P. Dimopoulos·R. Frezzotti·V. Gimenez·G. Herdoiza·V. Lubicz·G. Martinelli·C. Michael·D. Palao·G. C. Rossi·F. Sanfilippo·A. Shindler·S. Simula·C. Tarantino
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Abstract

We present a precise lattice QCD determination of the b-quark mass, of the B and Bs decay constants and first results for the B-meson bag parameters. For our computation we employ the so-called ratio method and our results benefit from the use of improved interpolating operators for the B-mesons. QCD calculations are performed with Nf = 2 dynamical light-quarks at four values of the lattice spacing and the results are extrapolated to the continuum limit. The preliminary results are mb(mb) = 4.35(12) GeV for the MSbar b-quark mass, fBs = 234(6) MeV and fB = 197(10) MeV for the B-meson decay constants, BBs(mb) = 0.90(5) and BB(mb) = 0.87(5) for the B-meson bag parameters.

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N. Carrasco, P. Dimopoulos, R. Frezzotti, V. Gimenez, G. Herdoiza, V. Lubicz, G. Martinelli, C. Michael, D. Palao, G. C. Rossi, F. Sanfilippo, A. Shindler, S. Simula, C. Tarantino. 2012-12-03. B-physics from lattice QCD...with a twist. https://arxiv.org/abs/1212.0301

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