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B-physics from HQET in two-flavour lattice QCD

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 نشر من قبل Fabio Bernardoni
 تاريخ النشر 2012
  مجال البحث
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We present our analysis of B physics quantities using non-perturbatively matched Heavy Quark Effective Theory (HQET) in Nf= 2 lattice QCD on the CLS ensembles. Using all-to-all propagators, HYP-smeared static quarks, and the Generalized Eigenvalue Problem (GEVP) approach with a conservative plateau selection procedure, we are able to systematically control all sources of error. With significantly increased statistics compared to last year, our preliminary results are mb (mb) = 4.22(10)(4)z GeV for the MS b-quark mass, and fB = 193(9)stat (4)_chi MeV and fBs = 219(12)stat MeV for the B-meson decay constants.

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