Speaker
Dr
CHIEN-YI MA
(NATIONAL TAIWAN UNIVERSITY)
Description
The Standard Model predicts the CP violation phase $\Phi^{\rm
SM}_{B_s}= \arg M_{12} \simeq \arg(V^*_{ts}V_{tb})$ in
$B_s$--$\bar B_s$ mixing is very small, of ${\cal}O(\lambda^2\eta)
\simeq -0.02$, any finite value of $\Phi_{B_s}$ measured at the
Tevatron would mean New Physics. Recent hints for finite
$\sin2\Phi_{B_s}$ have appeared from CDF and D$\O$ experiments at
the Tevatron Run II. We consider the possibility to account for it
with the 4th generation $t'$ quark. Considering recent direct
search bounds, we set the mass to be near the unitarity bound of
600 GeV. Combining the measurement values of $\Delta m_{B_s}$ with
${\cal B}(B_d\to X_s\ell^+\ell^-)$, together with typical
$f_{B_s}$ values, we find a sizable $\sin2\Phi^{\rm SM4}_{B_s}\sim
-0.3$. Using a typical value of $m_{b'}=580$ GeV, we get a narrow
range of values, $0.089<|V_{t'b}|<0.100$, from the constraints
$\Gamma(Z\to b\bar b)/\Gamma(Z\to{\rm hadrons})$, ${\cal
B}(K^+\to\pi^+\nu\bar\nu)$ and $\Delta m_{D^0}$. Finally, we use
the ZFITTER code to check the global fit deviation.
Primary author
Dr
CHIEN-YI MA
(NATIONAL TAIWAN UNIVERSITY)
Co-author
Prof.
WEI-SHU HOU
(NATIONAL TAIWAN UNIVERSITY)
