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B -> X_s l+ l- in the vectorlike quark model

M. R. Ahmady·M. Nagashima·A. Sugamoto
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Abstract

We extend the standard model by adding an extra generation of isosinglet up- and down-type quark pair which engage in weak interactions only via mixing with the three ordinary quark families. It is shown that the generalized $4\times 4$ quark mixing matrix, which is necessarily nonunitary, leads to nonvanishing flavor changing neutral currents. We then proceed to investigate various distributions and total branching ratio of the inclusive B -> X_s l+ l- (l =e,μ) rare B decays in the context of this model. It is shown that the shapes of the differential branching ratio and forward-backward asymmetry distribution are very sensitive to the value of the model parameters which are constrained by the experimental upper bound on BR(B -> X_s μ^+ μ^-). We also indicate that, for certain values of the dileptonic invariant mass, CP asymmetries up to 10% can be obtained.

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M. R. Ahmady, M. Nagashima, A. Sugamoto. 2001-08-01. B -> X_s l+ l- in the vectorlike quark model. https://doi.org/10.1063/1.1435654

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