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F_B from moving B mesons

S. Collins·G. Cowan·C. T. H. Davies·J. Hein·G. P. Lepage·C. Morningstar·J. Shigemitsue
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Abstract

We show results for the B meson decay constant calculated both for B mesons at rest and those with non-zero momentum and using both the temporal and spatial components of the axial vector current. It is an important check of lattice systematic errors that all these determinations of f_B should agree. We also describe how well different smearings for the B meson work at non-zero momentum - the optimal smearing has a narrow smearing for the b quark.

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S. Collins, G. Cowan, C. T. H. Davies, J. Hein, G. P. Lepage, C. Morningstar, J. Shigemitsue. 2001-10-01. F_B from moving B mesons. https://doi.org/10.1016/s0920-5632(01)01729-7

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