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O(alpha_s^2) corrections to b -> c decay at zero recoil

J. Franzkowski·J. B. Tausk
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Abstract

Analytic formulae are presented for the two-loop perturbative QCD corrections to b -> c decay at the zero recoil point, which are required for the extraction of |V_bc| from measurements of exclusive B -> D* l nu decays. The results are in agreement with those of Czarnecki and Melnikov. Some comments on the numerical evaluation of the diagrams involved are made.

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J. Franzkowski, J. B. Tausk. 1997-11-30. O(alpha_s^2) corrections to b -> c decay at zero recoil. https://doi.org/10.1007/s100520050296

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