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arXiv · 1401.2162

Effects of neutral $Z^{\prime}$ boson in $B_{s} \to ϕ\ell^{+} \ell^{-}$ decay with polarized $ϕ$ and the unpolarized and polarized $CP$ violation asymmetry

Ishtiaq Ahmed·M. Jamil Aslam·M. Ali Paracha
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Abstract

The effects of new neutral $Z^\prime$ boson in $B_{s}\toϕ\ell^{+}\ell^{-}$, when $ϕ$ is longitudinal or transverse polarized, are studied. In addition, the implications of $Z^{\prime}$ boson on the unpolarized and polarized $CP$ violation asymmetries, with reference to lepton, are also presented. It is observed that the branching ratio with polarized $ϕ$ are quite sensitive to the $Z^{\prime}$ contributions which are coming through the modification of Wilson coefficients $C^{eff}_{9}$ and $C_{10}$. Moreover, the off-diagonal elements of the chiral $Z^{\prime}$ couplings contain new weak phase $ϕ_{sb}$ that provide a new source of $CP$ violation. Keeping in view that in the FCNC transitions the $CP$ violation asymmetries are highly suppressed in the SM, we have studied the unpolarized and polarized $CP$ violation asymmetries in $B_{s}\toϕ\ell^{+}\ell^{-}$ decays. Our results indicate that these $CP$ violation asymmetries are remarkably significant and can attribute the any new physics coming through the $Z^{\prime}$ boson. It is hoped that the accurate measurements of these asymmetries will not only help us to establish NP but will also give a chance to determine the precise values of the coupling parameters of the $Z^{\prime}$ boson.

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Ishtiaq Ahmed, M. Jamil Aslam, M. Ali Paracha. 2014-06-13. Effects of neutral $Z^{\prime}$ boson in $B_{s} \to ϕ\ell^{+} \ell^{-}$ decay with polarized $ϕ$ and the unpolarized and polarized $CP$ violation asymmetry. https://doi.org/10.1103/physrevd.89.015006

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