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arXiv · hep-ph/0512258

Enhanced electroweak penguin amplitude in B-->VV decays

M. Beneke·J. Rohrer·D. Yang
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Abstract

We discuss a novel electromagnetic penguin contribution to the transverse helicity amplitudes in B decays to two vector mesons, which is enhanced by two powers of mB/Lambda relative to the standard penguin amplitudes. This leads to unique polarization signatures in penguin-dominated decay modes such as B-->rho K* similar to polarization effects in the radiative decay B-->K*gamma, and offers new opportunities to probe the magnitude and chirality of flavour-changing neutral current couplings to photons.

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M. Beneke, J. Rohrer, D. Yang. 2005-12-20. Enhanced electroweak penguin amplitude in B-->VV decays. https://doi.org/10.1103/physrevlett.96.141801

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