相关论文: Bounds on new physics from B_s mixing
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…
We report the observation of Bs-Bsbar oscillations from a time-dependent measurement of the Bs-Bsbar oscillation frequency Delta ms. Using a data sample of 1 fb^-1 of p-pbar collisions at sqrt{s}=1.96 TeV collected with the CDF II detector…
We discuss the implications of the recent measurement of the $B_s-\bar{B_s}$ oscillation frequency $\Delta M_s$ on the parameter space of R-parity violating supersymmetry. For completeness, we also discuss the bounds coming from leptonic,…
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…
We present the first measurement of the Bs-Bsbar oscillation frequency Delta m_s. We use 1 fb^-1 of data from p-pbar collisions at sqrt{s}=1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. The sample contains signals of…
A recent measurement by the D0 collaboration finds a like-sign di-muon charge asymmetry in the B system that is roughly 3 sigma larger than the value predicated by the Standard Model. This suggests new physics contributing to B-Bbar mixing.…
The Standard Model predicts a large width difference in the $B_s$ system. New physics can contribute significantly to the {\it mass} difference. If this contribution is CP violating, this will always result in a reduction of the {\it width}…
We consider the constraint of $B_s-\bar{B}_s$ mass difference, $\Delta m_s$, on an MSSM scenario with large flavor mixing. Even with this constraint, we show that a large deviation from the SM in CP asymmetries of $B_s \to KK$ decays is…
With 12.3 fb-1 collected by the BaBar experiment in 2001, the mixing parameter y = Delta(Gamma)/(2 Gamma) is determined from the ratio of the D0 lifetimes measured in the D0 --> K- pi+ and in the D0 --> K- K+ decay modes. The preliminary…
In this talk, I present new results [1] obtained from QCD spectral sum rules (QSSR), on the bag constant parameters entering in the analysis of the B^0_{(s)}-\bar B^0_{(s)} mass-differences. Taking the average of the results from the…
Using primarily experimental inputs for S(B -> psi Ks), Delta M_Bs, Delta M_Bd, BR(B -> tau nu) and epsilon_K along with necessary inputs from the lattice, we find that the measured value of sin(2 beta) is smaller than expectations of the…
This Letter describes the first determination of bounds on the CP-violation parameter 2*beta_s using Bs decays in which the flavor of the bottom meson at production is identified. The result is based on approximately 2,000 Bs -> J/psi phi…
Recent results using B_s -> J/Psi phi decays for measuring the CP violating phase, phi_s, and the decay width difference for the two mass eigenstates, Delta Gamma_s, are presented from the CDF and D0 experiments at the Fermilab Tevatron…
We study B_s-\bar{B}_s mixing in grand unified SO(10), SU(5) models where the mixings among the second and third generation squarks arise due to the existence of flavor violating sources in the Dirac and Majorana couplings which are…
The feasibility of determining $\Delta \Gamma_s / Gamma_s$ from $B_s \to D_s^{(*)+} D_s^{(*)-}$ decay branching fraction measurements at $e^+ e^-$ colliders running on the $\Upsilon$(5S) resonance is discussed. The expected accuracies of…
A measurement of Bs J/psi phi decay parameters, including the CP-violating weak phase phi_s and the decay width difference Delta Gamma_s is reported, using 4.9 fb-1 of integrated luminosity collected in 2011 by the ATLAS detector from LHC…
From an analysis of the flavor-tagged decay \bsdec we obtain the width difference between the $B_s^0$ light and heavy mass eigenstates, $\Delta \Gamma_s \equiv \Gamma_L - \Gamma_H = 0.19 \pm 0.07 {\rm (stat)}\thinspace ^{+0.02}_{-0.01} {\rm…
The weak phase \gamma can be determined using untagged B^0\to DK_S or B_s\to D\phi, D\eta^{(')} decays. In the past, the small lifetime difference y\equiv \Delta\Gamma/(2\Gamma) has been neglected in B^0, while the CP violating parameter…
The rare decays $B_{s(d)} \to \mu^+\mu^-$ play a key role for the testing of the Standard Model. An overview of the most recent theoretical predictions of the corresponding branching ratios is given, emphasizing that the sizable decay width…
Supersymmetric contributions to time independent asymmetry in $B^0_s \to J/\psi \phi$ process are analyzed in the view of the recent Tevatron experimental measurements. We show that the experimental limits of the mass difference $\Delta…