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arXiv · hep-ph/9304225

QCD Predictions for Lepton Spectra in Inclusive Heavy Flavour Decays

I. I. Bigi·M. Shifman·N. G. Uraltsev·A. Vainshtein
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Abstract

We derive the lepton spectrum in semileptonic beauty decays from a nonperturbative treatment of QCD; it is based on an expansion in $1/m_Q$ with $m_Q$ being the heavy flavour quark mass. The leading corrections arising on the $1/m_Q$ level are completely expressed in terms of the difference in the mass of the heavy hadron and the quark. Nontrivial effects appear in $1/m_Q^2$ terms affecting mainly the endpoint region; they are different for meson and baryon decays as well as for beauty and charm decays.

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I. I. Bigi, M. Shifman, N. G. Uraltsev, A. Vainshtein. 1993-04-06. QCD Predictions for Lepton Spectra in Inclusive Heavy Flavour Decays. https://doi.org/10.1103/physrevlett.71.496

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