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arXiv · 1012.4603

Symmetries in the angular distribution of exclusive semileptonic B decays

Ulrik Egede·Tobias Hurth·Joaquim Matias·Marc Ramon·Will Reece
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Abstract

We discuss a method to construct observables protected against QCD uncertainties based on the angular distribution of the exclusive Bd -> K(*0}(-> Kpi) l+ l- decay. We focus on the identification and the interpretation of all the symmetries of the distribution. They constitute a key ingredient to construct a set of so-called transverse observables. We work in the framework of QCD factorization at NLO supplemented by an estimate of power-suppressed Lambda/mb corrections. A discussion of the new physics properties of two of the transverse asymmetries, AT^{(2)} and AT^{(5)}, is presented. A comparison between the transverse asymmetry AT^{(2)} and the forward-backward asymmetry shows that AT^{(2)} emerges as an improved version of it.

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Ulrik Egede, Tobias Hurth, Joaquim Matias, Marc Ramon, Will Reece. 2010-12-21. Symmetries in the angular distribution of exclusive semileptonic B decays. https://arxiv.org/abs/1012.4603

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