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Study of FCNC mediated Z boson effect in the semileptonic rare baryonic decays $Λ_b \to Λl^+ l^- $

A. K. Giri·R. Mohanta
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Abstract

We study the effect of the FCNC mediated $Z$ boson in the rare semileptonic baryonic decays $Λ_b \to Λl^+ l^-$. We consider the model where the standard model fermion sector is extended by an extra vector like down quark, as a consequence of which it allows CP violating Z mediated flavor changing neutral current at the tree level. We find that due to this non-universal $Zbs $ coupling, branching ratios of the rare semileptonic $Λ_b$ decays are enhanced reasonably from their corresponding standard model values and the zero point of the forward backward asymmetry for $Λ_b \to Λμ^+ μ^-$ is shifted to the left.

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A. K. Giri, R. Mohanta. 2005-10-13. Study of FCNC mediated Z boson effect in the semileptonic rare baryonic decays $Λ_b \to Λl^+ l^- $. https://doi.org/10.1140/epjc%2Fs2005-02407-6

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