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Resummation of Nonperturbative Corrections to the Lepton Spectrum in Inclusive $B\to X\,\ell\,\barν$ Decays

Thomas Mannel·Matthias Neubert
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Abstract

We apply the operator product expansion to resum the leading nonperturbative corrections to the endpoint region of the lepton spectrum in inclusive semileptonic $B\to X_q\,\ell\,\barν$ decays, taking into account a finite quark mass $m_q$ in the final state. We show that both for $b\to c$ and $b\to u$ transitions, it is consistent to describe these effects by a convolution of the parton model spectrum with a fundamental light-cone structure function. The moments of this function are proportional to forward matrix elements of higher-dimension operators. The prospects for an extraction of the structure function from a measurement of the lepton spectrum are discussed.

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Thomas Mannel, Matthias Neubert. 1994-02-15. Resummation of Nonperturbative Corrections to the Lepton Spectrum in Inclusive $B\to X\,\ell\,\barν$ Decays. https://doi.org/10.1103/physrevd.50.2037

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