Related papers: The $B_s$ width difference beyond the Standard Mod…
About 90% of Bs-bar Bs pairs produced at the Upsilon(5s) resonance are initially Bs*-bar Bs* pairs which decay radiatively to Bs-bar Bs. This implies that the Bs pair will then be in an eigenstate of charge conjugation (i.e. C=-1) and…
$B_s - \bar B_s$ mixing has been measured recently by D0 and CDF. The range predicted in the standard model is consistent with data. However, the standard model central values for $\Delta M_{B_s}$ and also $\Delta M_ {B_d}$ are away from…
Recent developments concerning CP violation beyond the Standard Model are reviewed. The central target of this presentation is the $B$ system, as it plays an outstanding role in the extraction of CKM phases. Besides a general discussion of…
The BaBar and Belle experiments have recently presented evidence for D-Dbar mixing. We explain the following points: (i) The measurements imply width difference $y \sim 0.01$. In the limit of small CP violation, the CP-odd state is…
We argue that the observation of a sizable direct CP asymmetry A_{CP} in the inclusive decays B -> X_s gamma would be a clean signal of New Physics. In the Standard Model, A_{CP} can be calculated reliably and is found to be below 1% in…
The main challenge in the Standard Model calculation of the mass and width difference in $D^0 - \bar D^0$ mixing is to estimate the size of SU(3) breaking. We prove that mixing occurs in the Standard Model only at second order in SU(3)…
The standard CKM model can be tested and New Physics detected using only CP-violating phase measurements in B decays. This requires the measurement of a phase factor which is small in the Standard Model, in addition to the usual large…
We analyze the significant new model independent constraints on extensions of the standard model (SM) that follow from the recent measurements of the B^0_s-\bar B^0_s mass difference. The time-dependent CP asymmetry in B_s -> \psi\phi,…
We review mixing and CP violation in $D$ mesons, emphasizing the differences with the other pseudoscalar mesons in the Standard Model, and show that $D$ mesons can be useful to look for physics beyond the Standard Model.
At present, there are several measurements of $B$ decays that exhibit discrepancies with the predictions of the SM, and suggest the presence of new physics (NP) in $b \to s \mu^+ \mu^-$ transitions. Many NP models have been proposed as…
Within the Standard Model, $x_s$ (the mixing parameter in the $B_s-\bar B_s$ system) is constrained to the range $7 \leq x_s\leq 40$. We point out that if New Physics contributes significantly to $x_d$ (the mixing parameter in the $B_d-\bar…
We perform a study of the Standard Model (SM) fit to the mixing quantities $\Delta M_{B_s}$, and $\Delta \Gamma_{B_s}/\Delta M_{B_s}$ in order to bound contributions of New Physics to $B_s$ mixing. We then use this to explore the branching…
We discuss the effect of CP-violating $Zb\bar{b}$, $Zb\bar{b}G$ and $Zb\bar{b}\gamma$ couplings on the width $\Gamma(Z\rightarrow b\bar bX)$. The presence of such couplings leads in a natural way to an increase of this width relative to the…
In the model III 2HDM there are new CP violating phases which would affect the $B_{d,s}^0 - \bar{B}_{d,s}^0$ mixing. In this paper, we calculate the new physics contributions to the neutral B meson mass splitting $\Delta M_{B_q}$ (q=d, s)…
In this letter we introduce a possible measure of the size of CP violation in the Standard Model and its extensions, based on quantities invariant under the change of weak quark basis. We also introduce a measure of the ``average size'' of…
The study of CP violation in the B system allows us to perform quantitative tests of the CP symmetry in the Standard Model. Many precise measurements of the sides and angles of the Unitarity Triangle used to test the theory are made…
The measurement of CP asymmetries in charged B meson decays might provide the first demonstration of CP violation outside the K system. Among the usual three CP-odd phases $\alpha$, $\beta$ and $\gamma$, the phase $\gamma$ seems to be the…
The recently observed CP violation in B decay and $B$-$\ovar{B}$ mixing data put constraints on the mass of $W_R$ and the parameters of the right-handed current quark mixing matrix $V^R$ in $SU(2)_L \times SU(2)_R\times U(1)$ gauge model.…
A variety of CP violating asymmetries in $B^0$ decays is predicted in the Standard Model in terms of CKM (Cabibbo-Kobayashi-Maskawa) complex phases. These phases can also be determined from rate measurements of certain $B^+$ and $B^-$…
Present experiments in pursuit of the mass difference in the Bs-Bs(bar) system have put a lower bound on this quantity of $\Delta M_s > 14.9 ps^{-1}$ (at 95% C.L.). The same experiments also yield a local minimum in the log-likelihood…