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Measuring the Photon Helicity in Radiative B Decays

Michael Gronau·Yuval Grossman·Dan Pirjol·Anders Ryd
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Abstract

We propose a way of measuring the photon polarization in radiative B decays into K resonance states decaying to Kππ, which can test the Standard Model and probe new physics. The photon polarization is shown to be measured by the up-down asymmetry of the photon direction relative to the Kππdecay plane in the K resonance rest frame. The integrated asymmetry in K_1(1400)\to Kππ, calculated to be 0.34\pm 0.05 in the Standard Model, is measurable at currently operating B factories.

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Michael Gronau, Yuval Grossman, Dan Pirjol, Anders Ryd. 2001-12-23. Measuring the Photon Helicity in Radiative B Decays. https://doi.org/10.1103/physrevlett.88.051802

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