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Sensitivity of the squark flavor mixing to the CP violation of K, B0 and Bs mesons

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 Added by Kei Yamamoto Ms.
 Publication date 2013
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and research's language is English




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We study the sensitivity of the squark flavor mixing to the CP violating phenomena of $K$, $B^0$ and $B_s$ mesons in the framework of the split-family scenario, where the first and second family squarks are very heavy, ${cal O}(10)$TeV, on the other hand, the third family squark masses are at ${cal O}(1)$TeV. In order to constrain the gluino-sbottom-quark mixing parameters, we input the experimental data of the CP violations of $K$, $B^0$, and $B_s$ mesons, that is $epsilon_K$, $phi_d$, and $phi_s$. The experimental upper bound of the chromo-EDM of the strange quark is also input. In addition, we take account of the observed values $Delta M_{B^0}$, $Delta M_{B_s}$, the CKM mixing $|V_{ub}|$, and the branching ratio of $bto sgamma$. The allowed region of the mixing parameters are obtained as $|delta_{13}^{dL(dR)}|=0sim 0.01$ and $|delta_{23}^{dL(dR)}|=0sim 0.04$. By using these values, the deviations from the SM are estimated in the CP violations of the $B^0$ and $B_s$ decays. The deviation from the SM one is tiny in the CP asymmetries of $B^0to phi K_S$ and $B^0to eta K^0$ due to the chromo-EDM of the strange quark. On the other hand, the CP asymmetries $B_s to phi phi$ and $B_s to phi eta $ could be largely deviated from the SM predictions. We also predict the time dependent CP asymmetry of $B^0to K^0bar K^0$ and the semi-leptonic CP asymmetries of $B^0 to mu ^-X$ and $B_s to mu ^-X$. We expect those precise measurements at Belle II, which will provide us interesting tests for the squark flavor mixing.



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