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arXiv · 0807.4598

Exclusive $B \rar ρ\ell^+ \ell^-$ Decay in the Standard Model with Fourth--Generation

K. Zeynali·V. Bashiry
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Abstract

We investigate the influence of the fourth generation of quarks on the branching ratio, the CP-asymmetry and the polarization asymmetries in $B \rar ρ\ell^+ \ell^-$ decay. Taking $|V_{t'd}V_{t'b}|\sim 0.001$ with phase about $10^\circ$, which is consistent with the $sin2ϕ_1$ of the CKM and the $B_d$ mixing parameter $Δm_{B_d}$, we obtain that for both ($μ, τ$) channels the branching ratio is increased and the magnitude of CP-asymmetry and polarization asymmetries decreased by the mass and mixing parameters of the 4th generation of quarks . These results can serve as a good tool to search for new physics effects, precisely, to search for the fourth generation of quarks($t', b')$ via its indirect manifestations in loop diagrams.

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K. Zeynali, V. Bashiry. 2008-07-29. Exclusive $B \rar ρ\ell^+ \ell^-$ Decay in the Standard Model with Fourth--Generation. https://doi.org/10.1103/physrevd.78.033001

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