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arXiv · hep-ph/9307301

Supersymmetric $b \rightarrow s γ$ with Large Chargino Contributions

Robert Garisto·John N. Ng
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Abstract

Supersymmetric (SUSY) theories are often thought to give large branching ratios for $b \rightarrow s γ$ from charged Higgs loops. We show that in many cases chargino loop contributions can cancel those of the Higgs, and SUSY can give $B(b \rightarrow s γ)$ at or below the \SM\ prediction. We show this occurs because the large stop mass splittings usually found in SUSY break a GIM mechanism suppression. These effects are strongly enhanced by large $\tanβ$, so that $B(b \rightarrow s γ)$ is very sensitive to the value of $\tanβ$, contrary to what has been claimed. We also note that the supergravity relation $B_0 = A_0-1$ is somewhat disfavored over the general case.

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Robert Garisto, John N. Ng. 1993-07-20. Supersymmetric $b \rightarrow s γ$ with Large Chargino Contributions. https://doi.org/10.1016/0370-2693(93)91627-y

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