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arXiv · hep-ph/9312234

Cancellation of power enhancements in non-spectator decays

U. Aglietti
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Abstract

Exclusive non-spectator decay rates of beauty hadrons contain power enhancements of the form (m_b/m)^2 and m_b/m, where m_b is the b-quark mass and m is a light quark mass. An implicit argument has been recently given according to which these singularities cancel in the totally inclusive decay width. We present in this note a completely explicit computation of the diagrams containing power enhancements. Our results agree with the previous general conclusion.

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U. Aglietti. 1993-12-06. Cancellation of power enhancements in non-spectator decays. https://doi.org/10.1016/0370-2693(94)90042-6

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