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Estimates of Long-distance Contributions to the $B_s \to γγ$ Decay

Debajyoti Choudhury·John Ellis
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Abstract

We present first calculations of new long-distance contributions to $B_s \to γγ$ decay due to intermediate $D_s$ and $D_s^*$ meson states. The relevant $γ$ vertices are estimated using charge couplings and transition moment couplings. Within our uncertainties, we find that these long-distance contributions could be comparable to the known short-distance contributions. Since they have different Cabibbo-Kobayashi-Maskawa matrix-element factors, there may be an interesting possibility of observing CP violation in this decay.

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Debajyoti Choudhury, John Ellis. 1998-04-15. Estimates of Long-distance Contributions to the $B_s \to γγ$ Decay. https://doi.org/10.1016/s0370-2693(98)00679-0

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