Double Lepton Polarization in ${\Lambda }_b-->\Lambda l^{+}{l}^{-}$ Decay in the Standard Model with Fourth Generations Scenario

Abstract

This study investigates the influence of the fourth generation quarks on the double lepton polarizations in Λ_b --> Λ\ell^+ \ell^- decay by taking |V^\ast_{t's}V_{t'b}|= 0.005,0.01,0.02,0.03 with phase \{60^\circ,90^\circ,120^\circ\}. We will try to obtain a constrain on the mass of the 4th generation top like quark t', which is consistent with the $b--> s\ell^+\ell^- rate . With the above mentioned parameters, we will try to show that the double lepton(muon, tau) polarizations are quite sensitive to the existence of fourth generation. It can serve as a good tool to search for new physics effects, precisely, to search for the fourth generation quarks(t', b') via its indirect manifestations in loop diagrams.

36 pages, 33 figures

Cited by in corpus (3)

• The Effects of Fourth Generation on the double Lepton Polarization in B \rar K \ell^+ \ell^- decay
• CP-Conserving Unparticle Phase Effects on the Unpolarized and Polarized Direct CP Asymmetry in $b\to d{\ell }^{+}{\ell }^{-}$ Transition
• Exclusive $B \rar ρ\ell^+ \ell^-$ Decay in the Standard Model with Fourth--Generation