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arXiv · 1105.3679

Limits on New Physics from exclusive $B \to D^{(*)}\ell \barν$ Decays

Sven Faller·Thomas Mannel·Sascha Turczyk
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Abstract

We consider the exclusive decays $B \to D^{(*)}\,\ell \barν$ and study the effect of non $V-A$ structures on the observables. We extend the standard model hadronic current by additional right-handed vector as well as left- and right-handed scalar and tensor contributions and calculate the decay rates including the perturbative corrections up to order $α_s$. Using the data of the exclusive semileptonic $b \to c $ decays and recent calculations of the form factors at the non-recoil point we discuss the constraints to the wrong helicity admixtures in the hadronic current.

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Sven Faller, Thomas Mannel, Sascha Turczyk. 2011-05-18. Limits on New Physics from exclusive $B \to D^{(*)}\ell \barν$ Decays. https://doi.org/10.1103/physrevd.84.014022

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