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Mixing-induced CP Asymmetries in Radiative B Decays in and beyond the Standard Model

David Atwood·Michael Gronau·Amarjit Soni
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Abstract

In the Standard Model (SM) the photon in radiative $\bar B^0$ and $\bar B_s$ decays is predominantly left-handed. Thus, mixing induced CP asymmetries in $b\to sγ$ and $b\to dγ$ are suppressed by $m_s/m_b$ and $m_d/m_b$, respectively, and are very small. In many extensions of the SM, such as the left-right symmetric model (LRSM), SU(2)xU(1) models with exotic fermions and SUSY, the amplitude of right-handed photons grows proportional to the virtual heavy fermion mass, which can lead to large asymmetries. As an example, in the LRSM, asymmetries larger than 50% are possible even when radiative decay rate measurements agree with SM predictions.

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David Atwood, Michael Gronau, Amarjit Soni. 1997-04-09. Mixing-induced CP Asymmetries in Radiative B Decays in and beyond the Standard Model. https://doi.org/10.1103/physrevlett.79.185

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