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arXiv · hep-ph/0005069

Extracting and using photon polarization information in radiative B decays

Yuval Grossman·Dan Pirjol
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Abstract

We discuss the uses of conversion electron pairs for extracting photon polarization information in weak radiative B decays. Both cases of leptons produced through a virtual and real photon are considered. Measurements of the angular correlation between the $(Kπ)$ and $(e^+e^-)$ decay planes in $B\to K^*(\to Kπ)γ^{(*)}(\to e^+e^-)$ decays can be used to determine the helicity amplitudes in the radiative $B\to K^*γ$ decay. A large right-handed helicity amplitude in $\bar B$ decays is a signal of new physics. The time-dependent CP asymmetry in the $B^0$ decay angular correlation is shown to measure $\sin 2β$ and $\cos 2β$ with little hadronic uncertainty.

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Yuval Grossman, Dan Pirjol. 2000-05-19. Extracting and using photon polarization information in radiative B decays. https://doi.org/10.1088/1126-6708%2F2000%2F06%2F029

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