Related papers: $B_s$ Mixing and New Physics in hadronic $b \to s …
Using the hadronic matrix elements from the lattice, B_K and xi_s, involving only the 4-quark operators for Delta flavor (F) = 2 Hamiltonian relevant for K, B_d and B_s mixing, along with V_cb, we deduce a non-trivial constraint on the SM,…
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…
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…
Measurements of the $B_s^0$--$\bar{B}_s^0$ mixing phase $\phi_s$ appear to be converging towards the SM prediction, suggesting that contributions from New Physics (NP), if present, are small. This poses the question of whether smallish NP…
Within the standard model (SM), the time dependent CP asymmetries in B -> psi K_S, B -> eta' K_S and B -> phi K_S are expected to give the same result i.e. sin (2 beta). However recent measurements of the mixing induced CP asymmetries in B…
We show that the recent measurements of $B_s-\bar{B}_s$ mass difference, $\Delta m_s$, by D{\O} and CDF collaborations give very strong constraints on MSSM scenario with large flavor mixing in the LL and/or RR sector of down-type squark…
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 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 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…
We analyse three different New Physics scenarios for Delta F=2 flavour-changing neutral currents in the quark sector in the light of recent data on neutral-meson mixing. We parametrise generic New Physics contributions to B_q-Bbar_q mixing…
We combine all the available experimental information on Bs mixing, including the very recent tagged analyses of Bs to J/Psi phi by the CDF and D0 collaborations. We find that the phase of the Bs mixing amplitude deviates more than 3 sigma…
Recently two hints for new physics have emerged: The B_s mixing phase phi_s and the rate of D_s -> (mu,tau) nu exposing a discrepancy of \sim 3 sigma and 3.8 sigma deviation from the Standard Model respectively. Moreover the difference of…
Two recent experimental developments, when combined, may have far reaching implications. $S_{\phi K_S} < 0$, if confirmed, would imply large $s$-$b$ mixing, a new CP phase, and right-handed dynamics. Large $\Delta m_{B_s}$ would be likely,…
I discuss three B physics results with potential for exhibiting new flavour-changing interactions: (1) the time-dependent CP asymmetry in B\to J/\psi K_S decay; (2) branching fractions and CP asymmetries in B\to \pi\pi, \pi K decays; (3)…
Motivated by the possibility of ${\cal S}_{\phi K_S}<0$, we study the implications for $B_s$ meson system. In a specific model that realizes ${\cal S}_{\phi K_S}<0$ with large $s$-$b$ mixing, right-handed dynamics and a new CP phase, we…
Measurements performed at the Tevatron of both the like-sign dimuon charge asymmetry in B_d,s-meson samples and the mixing-induced CP asymmetry in B_s -> J/psi phi depart from their standard model (SM) predictions. This could be an…
If the weak phase of B_s-anti B_s mixing (2 beta_s) is found to be significantly different from zero, this is a clear signal of new physics (NP). However, if such a signal is found, we would like an unambiguous determination of 2 beta_s in…
A 4th generation could be consistent with the recently measured $\Delta m_{B_s}$ as well as ${\cal B}(b\to s\ell^+\ell^-)$, which are SM-like, but generate large $\sin2\Phi_{B_s} \simeq -0.5$ to -0.7. The sign is determined by the hint for…
The recent observation of the mass difference in $B_s$ system seems to be not in complete agreement with the corresponding standard model value. We consider the model with an extra vector like down quark to explain this discrepancy and…
Recently, the CDF and D0 collaborations measured indirect CP violation in Bs -> J/psi phi and found a hint of a signal. If taken at face value, this can be interpreted as a nonzero phase of Bs-Bsbar mixing (beta_s), in disagreement with the…