标准模型预测非常小的CP破坏阶段$\sin2Φ^{\rm SM}_{B_s} \simeq -0.04$ %= \arg M_{12} \simeq \arg \，（V^*_{ts} V_{tb}）^2 $ in $ B_s $--$ \bar B_s $ mixing. %, i.e. of order $ λ^2η $. Any finite value of $ Φ_{B_s} $ measured at the Tevatron would imply New Physics. With recent hints for finite $ \sin 2Φ_{B_s} $, % have appeared from CDF and DØ\, experiments at the Tevatron, we reconsider the possibility of a 4th generation. As recent direct search bounds have become considerably heavier than 300 GeV, we take the $ t' $ mass to be near the unitarity bound of 500 GeV. Combining the measured values of $ Δ m_{B_s} $ with $ { \cal B}（B \to X_s \ell^+ \ell^-）$, together with typical $ f_{B_s} $ values, we find a sizable $ \sin 2Φ^{$ GeV, we extract the range % a range of values, $ SM4}_{B_s} $ GeV, we extract the range % a range of values, $-0.33 $. Using %a typical value of $ m_{b'} = 480 $ GeV, we extract the range % a range of values, $ 0.06 <|V_{t'b}| < 0.13 $ from the constraints of $ Γ（Z \to b \bar b）$, $ Δ m_{D} $ and $ { \cal B}（K^+ \to π^+ν \bar ν）$. A future measurement of $ { \cal B}（K_L \to π ^0 ν \bar ν）$ will determine $ V_{t'd} $.
英文摘要：
The Standard Model predicts a very small CP violation phase $\sin2Φ^{\rm SM}_{B_s} \simeq -0.04$%= \arg M_{12} \simeq \arg\,(V^*_{ts}V_{tb})^2$ in $B_s$--$\bar B_s$ mixing. %, i.e. of order $λ^2η$. Any finite value of $Φ_{B_s}$ measured at the Tevatron would imply New Physics. With recent hints for finite $\sin2Φ_{B_s}$, % have appeared from CDF and DØ\, experiments at the Tevatron, we reconsider the possibility of a 4th generation. As recent direct search bounds have become considerably heavier than 300 GeV, we take the $t'$ mass to be near the unitarity bound of 500 GeV. Combining the measured values of $Δm_{B_s}$ with ${\cal B}(B \to X_s\ell^+\ell^-)$, together with typical $f_{B_s}$ values, we find a sizable $\sin2Φ^{\rm SM4}_{B_s} \sim -0.33$. Using %a typical value of $m_{b'} = 480$ GeV, we extract the range % a range of values, $0.06 < |V_{t'b}| < 0.13$ from the constraints of $Γ(Z\to b\bar b)$, $Δm_{D}$ and ${\cal B}(K^+\toπ^+ν\barν)$. A future measurement of ${\cal B}(K_L\toπ^0ν\barν)$ will determine $V_{t'd}$.
Mass pattern of the SM fermions is one of the most important mysterious in particle physics. Flavor Democracy could shed light on this mystery. Addition of isosinglet quark and isosinglet lepton give opportunity to obtain masses of charged leptons and quarks of the 2nd and 3rd family due to small deviations of full Flavor Democracy.
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We revisit two-color, two-flavor chiral perturbation theory at finite isospin and baryon density. We investigate the phase diagram obtained varying the isospin and the baryon chemical potentials, focusing on the phase transition occurring when the two chemical potentials are equal and exceed the pion mass (which is degenerate with the diquark mass). In this case, there is a change in the order parameter of the theory that does not lend itself to the standard picture of first order transitions. We explore this phase transition both within a Ginzburg-Landau framework valid in a limited parameter…
