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arXiv · hep-ph/0005303

The $b\to sγ$ decay in SUSY models with non-universal A-terms

Abstract

We analyse the predictions for the inclusive branching ratio for $b\to sγ$ decay in a class of string-inspired SUSY models with non-universal soft-breaking A-terms. These models are particularly interesting since the non-universality of the A-terms plays an important role in providing new significant contributions to CP violation effects in kaon physics while respecting the severe bounds on electric dipole moments. We show that $b\to sγ$ do not severely constrain the non-universality of these models. In particular, at low $\tanβ$ $(\tanβ\simeq 2)$, our predictions are close to the universal case. For large $\tanβ$ ($\tanβ\gsim 15$),the effect of non-universality is enhanced and stronger constraints hold. We find that the parameter regions which are important for generating sizeable contribution to $ε'/ε$, of order $2 \times 10^{-3}$, are not excluded.

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BibTeXRIS

E. Gabrielli, S. Khalil, E. Torrente-Lujan. 2000-05-30. The $b\to sγ$ decay in SUSY models with non-universal A-terms. https://doi.org/10.1016/s0550-3213(00)00597-6

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