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arXiv · 1712.04959

Gluino-mediated electroweak penguin with flavor-violating trilinear couplings

Motoi Endo·Toru Goto·Teppei Kitahara·Satoshi Mishima·Daiki Ueda·Kei Yamamoto
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Abstract

In light of a discrepancy of the direct $CP$ violation in $K\toππ$ decays, $\varepsilon'/\varepsilon_K$, we investigate gluino contributions to the electroweak penguin, where flavor violations are induced by squark trilinear couplings. Top-Yukawa contributions to $ΔS = 2$ observables are taken into account, and vacuum stability conditions are evaluated in detail. It is found that this scenario can explain the discrepancy of $\varepsilon'/\varepsilon_K$ for the squark mass smaller than 5.6 TeV. We also show that the gluino contributions can amplify $\mathcal{B}(K \to πν\overlineν)$, $\mathcal{B}(K_S \to μ^+ μ^-)_{\rm eff}$ and $ΔA_{\rm CP}(b\to sγ)$. Such large effects could be measured in future experiments.

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Motoi Endo, Toru Goto, Teppei Kitahara, Satoshi Mishima, Daiki Ueda, Kei Yamamoto. 2018-04-03. Gluino-mediated electroweak penguin with flavor-violating trilinear couplings. https://doi.org/10.1007/jhep04(2018)019

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