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arXiv · hep-ph/9311339

The Baffling Semileptonic Branching Ratio of $B$ Mesons

I. Bigi·B. Blok·M. Shifman·A. Vainshtein
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Abstract

The apparent gap between the measured and the expected value for the semileptonic branching ratio of $B$ mesons has become more serious over the last year. This is due to the improved quality of the data and to the increasing maturity of the theoretical treatment of non-perturbative corrections. We discuss various theoretical options to reduce the semileptonic $B$ branching ratio; among the more spectacular resolutions of the apparent puzzle is the possibility of an unorthodox enhancement in non-perturbative corrections or even of an intervention by `New Physics'. Phenomenological implications of such scenarios are pointed out.

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I. Bigi, B. Blok, M. Shifman, A. Vainshtein. 1993-12-06. The Baffling Semileptonic Branching Ratio of $B$ Mesons. https://doi.org/10.1016/0370-2693(94)91239-4

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