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arXiv · 2205.03410

A first glance to the kinematic moments of $B \to X_c \ell \nu$ at third order

Matteo Fael·Kay Schönwald·Matthias Steinhauser
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Abstract

We study the impact of third-order QCD corrections for several kinematic moments of the inclusive semileptonic $B$ decays, to first order in the $1/m_b$ expansion. We consider the first four moments of the charged-lepton energy $E_\ell$ spectrum, the total leptonic invariant mass $q^2$ and the hadronic invariant mass $M_X^2$. No experimental cuts are applied. Our analytic results are obtained via an asymptotic expansion around the limit $m_b \simeq m_c$. After converting the scheme for the bottom mass to the kinetic scheme we compare the size of higher QCD corrections to the contributions from $1/m_b^2$ and $1/m_b^3$ power corrections and to the relative uncertainties.

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Matteo Fael, Kay Schönwald, Matthias Steinhauser. 2022-05-06. A first glance to the kinematic moments of $B \to X_c \ell \nu$ at third order. https://doi.org/10.1007/jhep08(2022)039

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