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Two-loop QCD corrections to semileptonic b-quark decays near maximum recoil

A. Pak·I. Blokland·A. Czarnecki
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Abstract

Two-gluon radiative corrections to the $b\to c\ellν$ decay width have been computed analytically as an expansion in terms of \frac{m_c}{m_b} << 1 in the kinematical limit of zero lepton invariant mass. The obtained results match smoothly with a previously known expansion around (1 - \frac{m_c}{m_b} << 1. Together they describe the process $b\to c\ellν$ for all mass ratios \frac{m_c}{m_b}.

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A. Pak, I. Blokland, A. Czarnecki. 2006-04-26. Two-loop QCD corrections to semileptonic b-quark decays near maximum recoil. https://doi.org/10.1103/physrevd.73.114009

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