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arXiv · 1206.2296

B-> D* zero-recoil formfactor and the heavy quark expansion in QCD: a systematic study

Paolo Gambino·Thomas Mannel·Nikolai Uraltsev
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Abstract

We present a QCD analysis of heavy quark mesons focussing on the B -> D* formfactor at zero recoil, F_D*(1). An advanced treatment of the perturbative corrections in the Wilsonian approach is presented. We estimate the higher-order power corrections to the OPE sum rule and describe a refined analysis of the nonresonant continuum contribution. In the framework of a model-independent approach, we show that the inelastic contribution in the phenomenological part of the OPE is related to the mQ-dependence of the hyperfine splitting and conclude that the former is large, lowering the prediction for F_D*(1) down to about 0.86. This likewise implies an enhanced yield of radial and D-wave charm excitations in semileptonic B decays and alleviates the problem with the inclusive yield of the wide excited states. We also apply the approach to the expectation values of dimension 7 and 8 local operators and to a few other issues in the heavy quark expansion.

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Paolo Gambino, Thomas Mannel, Nikolai Uraltsev. 2012-06-11. B-> D* zero-recoil formfactor and the heavy quark expansion in QCD: a systematic study. https://doi.org/10.1007/jhep10(2012)169

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