Flavor and CP Violation with Fourth Generations Revisited

Abstract

The Standard Model predicts a very small CP violation phase $\sin 2{\Phi }_{B_s}^{\mathrm{SM}}\simeq -0.04$%= \arg M_{12} \simeq \arg\,(V^*_{ts}V_{tb})^2$in$B_s$--$\bar B_s$mixing.$\lambda^2\eta$.Anyfinitevalueof$\Phi_{B_s}$measuredattheTevatronwouldimplyNewPhysics.Withrecenthintsforfinite$\sin2\Phi_{B_s}$,$t'$masstobeneartheunitarityboundof500GeV.Combiningthemeasuredvaluesof$\Delta m_{B_s}$with${\cal B}(B \to X_s\ell^+\ell^-)$,togetherwithtypical$f_{B_s}$values,wefindasizable$\sin2\Phi^{\rm SM4}_{B_s} \sim -0.33$.Using$m_{b'} = 480$GeV,weextracttherange$0.06 < |V_{t'b}| < 0.13$fromtheconstraintsof$\Gamma(Z\to b\bar b)$,$\Delta m_{D}$and${\cal B}(K^+\to\pi^+\nu\bar\nu)$.Afuturemeasurementof${\cal B}(K_L\to\pi^0\nu\bar\nu)$willdetermine$V_{t'd}$.

Comments: 8 pages, 11 figures