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Probing photon helicity in radiative B decays via charmonium resonance interference

Mathias Knecht·Thomas Schietinger
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Abstract

We investigate a new method to probe the helicity of the photon emitted in the b -> s gamma transition. The method relies on the observation of interference effects between two resonance contributions, B -> K*(K gamma) gamma and B -> eta_c(gamma gamma) K or B -> chi_c0(gamma gamma) K to the same final state K gamma gamma. Decays of the type B -> K_res(K gamma) gamma dominate the B -> K gamma gamma yield throughout most of the phase space, and may be accessible at current B meson facilities already.

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Mathias Knecht, Thomas Schietinger. 2006-03-08. Probing photon helicity in radiative B decays via charmonium resonance interference. https://doi.org/10.1016/j.physletb.2006.02.004

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