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Light Rays of New Physics: CP Violation in B -> Xs gamma Decays

Matthias Neubert
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Abstract

The observation of a sizable CP asymmetry in the inclusive decays B -> Xs gamma would be a clean signal of New Physics. In the Standard Model, this asymmetry is below 1 % in magnitude. In extensions of the Standard Model with new CP-violating couplings, large asymmetries are possible without conflicting with the experimental value of the B -> Xs gamma branching ratio. In particular, large asymmetries arise naturally in models with enhanced chromo-magnetic dipole transitions. Some generic examples of such models are explored and their implications for the semileptonic branching ratio and charm yield in B decays discussed.

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Matthias Neubert. 1998-09-11. Light Rays of New Physics: CP Violation in B -> Xs gamma Decays. https://doi.org/10.1016/s0920-5632(99)00175-9

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