相关论文: B^0_{d,s} - \bar{B}^0_{d,s} mixing in the model II…
Recently, the CDF and D{\O} collaborations have claimed that the CP violating phase in $B_s^0-\bar{B}_s^0$ mixing is large, which is contrary to the expectations in the Standard Model. Such a large phase suggests New Physics contributions…
As is well known, $B^0_{d,s}$--$\bar B^0_{d,s}$ mixing offers a profound probe into the effects of physics beyond the Standard Model. The data obtained at the $e^+e^-$ $B$ factories have already provided valuable insights into the…
New physics contributions to B_s-\bar{B}_s mixing can be parametrized by the size (r_s^2) and the phase (2\theta_s) of the total mixing amplitude relative to the Standard Model amplitude. The phase has so far been unconstrained. We first…
We study the implication of the recent $\Delta m_s$ measurement on $ b \to s \bar{q} q$ transitions. We show that it is possible, in the presence of a flavour symmetry, that the phase in $B_s$ mixing may be unobservable even with new CP odd…
We calculate the new physics contributions to the neutral $B_d^0$ and $B_s^0$ meson mass splitting $\Delta M_d$ and $\Delta M_s$ induced by the box diagrams involving the charged-Higgs bosons in the top quark two-Higgs doublet model…
We argue that a small or large CP-violating asymmetry {\cal A}_{\psi K_S} in B^0_d vs \bar{B}^0_d --> J/\psi K_S decays, which seems to be favored by the recent BaBar or Belle data, might hint at the existence of new physics in B^0_d -…
We analyse present constraints on the SM parameter space and derive, in a model independent way, various bounds on New Physics contributions to $B_d^0$--$\bar B_d^0$ and $B_s^0$--$\bar B_s^0$ mixings. Our analyses include information on a…
In many extensions of the standard model, new physics is possible to contribute significantly to B^0_s-\bar{B}^0_s mixing. We show that the effect of new physics, both its phase information and its magnitude, can be isolated from…
Recently, the CDF collaboration has reported a measurement of the CP asymmetry in the $B\to\psi K_S$ decay: $a_{\psi K_S}=0.79^{+0.41}_{-0.44}$. We analyze the constraints that follow from this measurement on the size and the phase of…
In this paper, we calculated the next-to-leading order (NLO) new physics contributions to the mass splitting $\dmd$ and the branching ratio $\brbxsga$ induced by the charged Higgs loop diagrams in the third type of two-Higgs-doublet models…
We consider three possible scenarios of new physics in B^0_d-\bar{B}^0_d mixing and propose a simple framework for analyzing their effects. This framework allows us to study the CP asymmetry in semileptonic B_d decays ({\cal A}_{SL}) and…
We review experimental and theoretical aspects of CP violation in the $B_s^0$-system. In that respect we present updates for the mixing parameters of the $B_s^0$ mesons expected in the Standard Model (SM): the mass difference $\Delta…
It is shown that in the approximation of $|\frac{q}{p}|$=1 the CP violation in $B^0_{d,s} \to l^+ l^-$ decays vanishes in SM. In a 2HDM with CP violating phases and MSSM the CP asymmetries depend on the parameters of models and can be as…
Combining the measured B_s mixing with b \to s\ell^+\ell^- rate data, we find a sizable 4 generation t' quark effect is allowed, for example with m_{t'} \sim 300 GeV and V_{t's}^*V_{t'b} \sim 0.025 e^{\pm i 70^\circ}, which could underly…
The B-meson system offers interesting probes for the search of physics beyond the Standard Model. After addressing possible signals of new-physics contributions to the B -> phi K and B -> pi K decay amplitudes, we focus on the data for…
We point out that the observed CP violation in Bd - bar{Bd} mixing, taking into account the measured ratio Delta Md / Delta Ms, the recently improved lattice value of the non-perturbative parameter BK and an additional effective suppression…
Precise measurements of the $B_s^0 - \overline{B}_s^0$ mixing parameters provide a powerful test of the Standard Model, offering potential hints to new physics. The LHCb collaboration has performed updated measurements of the $CP$-violating…
In this work we study the CP violation for $\bar{B^0}\to J/\psi K_s$ and $\bar{B^0}\to \phi K_s$ up to leading and next-to-leading order QCD corrections in the standard model, two-Higgs-doublet model and the minimal supersymmetric extension…
CP violation in neutral $B$ meson oscillations is an experimental observable that could be directly related to the baryon asymmetry of the Universe through the $B$-Mesogenesis mechanism. As this phenomenon is highly suppressed in the…
We perform model-independent statistical analyses of three scenarios accommodating New Physics (NP) in Delta F=2 flavour-changing neutral current amplitudes. In a scenario in which NP in B_d-B_d-bar and B_s-B_s-bar is uncorrelated, we find…