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arXiv · 2102.03343

Perturbative corrections to power suppressed effects in $\bar B\to X_u\ell\nu$

Bernat Capdevila·Paolo Gambino·Soumitra Nandi
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Abstract

We compute the $O(\alpha_s)$ corrections to the Wilson coefficients of the dimension five operators in inclusive semileptonic $B$ decays in the limit of a massless final quark. Our calculation agrees with reparameterization invariance and with previous results for the total width and places constraints on the shape functions that enter those decays.

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Bernat Capdevila, Paolo Gambino, Soumitra Nandi. 2021-02-05. Perturbative corrections to power suppressed effects in $\bar B\to X_u\ell\nu$. https://doi.org/10.1007/jhep04(2021)137

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