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arXiv · 1508.07595

Precise Ratios of Decay Constants of Vector over Pseudoscalar $B_{(s)}$ Mesons

Wolfgang Lucha·Dmitri Melikhov·Silvano Simula
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Abstract

The relative magnitude of the decay constants of the pseudoscalar and vector beauty mesons poses (in contrast to the case of charmed mesons) a long-standing puzzle. We revisit this problem within the framework of our recent improvements of the QCD sum-rule formalism for relating observable properties of mesons to quantum chromodynamics and are led to conclude that the decay constants of the beauty vector mesons are undoubtedly smaller than those of their pseudoscalar counterparts.

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Wolfgang Lucha, Dmitri Melikhov, Silvano Simula. 2015-08-30. Precise Ratios of Decay Constants of Vector over Pseudoscalar $B_{(s)}$ Mesons. https://arxiv.org/abs/1508.07595

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