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arXiv · 1211.0866

A one-loop study of matching conditions for static-light flavor currents

Dirk Hesse·Rainer Sommer
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Abstract

Heavy Quark Effective Theory (HQET) computations of semi-leptonic decays, e.g. B -> pi l nu, require the knowledge of the parameters in the effective theory for all components of the heavy-light flavor currents. So far non-perturbative matching conditions have been employed only for the time component of the axial current. Here we perform a check of matching conditions for the time component of the vector current and the spatial component of the axial vector current up to one-loop order of perturbation theory and to lowest order of the 1/m-expansion. We find that the proposed observables have small higher order terms in the 1/m-series and are thus excellent candidates for a non-perturbative matching procedure.

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Dirk Hesse, Rainer Sommer. 2012-11-05. A one-loop study of matching conditions for static-light flavor currents. https://doi.org/10.1007/jhep02(2013)115

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