Related papers: Possibility of large lifetime differences in neutr…
Using events in which one of two neutral B mesons from the decay of an Y(4S) resonance is fully reconstructed, we set limits on the lifetime difference between the two neutral-B mass eigenstates and on CP, T, and CPT violation in B0-B0bar…
Motivated by results from the LHC and dark matter searches, we study the possibility of phenomenologically viable R-parity violation in $SU(5)$ GUT models from a top-down point of view. We show that in contrast to the more model dependent…
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 discuss two independent issues about the baryon asymmetry of the universe. First, assuming that it is generated by an unspecified source at high temperatures, we study the effects of non-perturbative $SU(2)_W$ dynamics above the…
CP-violating effects in non-leptonic $B_s$-meson decays are reviewed. Special emphasis is given to implications arising from the width difference $\Delta\Gamma_s$ between the $B_s$ mass eigenstates. If $\Delta\Gamma_s$ is found to be…
We analyse the present experimental evidence for a complex CKM matrix, even allowing for New Physics contributions to $\epsilon_{K}$, $a_{J/\Psi K_{S}}$%, $\Delta M_{B_{d}}$, $\Delta M_{B_{s}}$, and the $\Delta I=1/2$ piece of $% B\to \rho…
The calculation of QCD corrections to the width difference Delta Gamma in the B_s meson system is presented. The next-to-leading order corrections reduce the dependence on the renormalization scale significantly and allow for a meaningful…
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…
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 study possible effects of supersymmetry (SUSY) in CP asymmetries in non-leptonic $B_{d,s}$ decays in a variety of SUSY flavour models considered in literature. We use both mass insertion and vertex mixing methods to calculate…
The recent measurements of the $B_s$ mass difference $\Delta M_s$ by the CDF and D{\O} collaborations are roughly consistent with the Standard Model predictions, therefore, these measurements will afford an opportunity to constrain new…
Motivated by the recent determination of the top quark mass by the CDF collaboration, $\mt =174 \pm 10 ^{+13}_{-12}$ GeV, we review and update the constraints on the parameters of the quark flavour mixing matrix $V_{CKM}$ in the standard…
After reviewing the theoretical uncertainties entering the Standard Model determination of the mass difference of the neutral $B_s$-$\bar B_s$ meson system, $\Delta M_s^{\rm SM}$, we discuss the implications of its updated value for new…
We use the heavy quark expansion to investigate the width difference $\Delta\Gamma_{B_s}$ between the $B_s$ mass eigenstates. The corrections of ${\cal O}(\Lambda_{QCD}/m_b)$ and ${\cal O}(m_s/m_b)$ to the leading order expression in the…
B-hadron physics plays a fundamental role to test and improve our understanding of flavor dynamics within and beyond the Standard Model. Of particular phenomenological interest are beauty hadron lifetime ratios and, width differences and…
The decay $B^0_s\to\mu^+\mu^-$ is a key probe for the search of physics beyond the Standard Model. While the current measurements of the corresponding branching ratio agree with the Standard Model within the uncertainties, significant…
We conduct a systematic study of the impact of new physics in quark-level $b \to c \bar{c} s$ transitions on $B$-physics, in particular rare $B$-decays and $B$-meson lifetime observables. We find viable scenarios where a sizable effect in…
We investigate the effect of scalar leptoquarks and family non-universal $Z^\prime$ boson on the rare leptonic decays of $B_{s, d}^*$ mesons, mediated by the FCNC transitions $b \to (d, s) l^+ l^-$. They are sensitive to a variety of new…
We analyze the one loop corrections to leptonic W and Z decays in an R-parity violating extension to the Minimal Supersymmetric Standard Model (MSSM). We find that lepton universality violation in the Z line-shape variables alone would…
The phenomenon of $B^0_q$-$\bar{B}^0_q$ mixing ($q=d,s$) provides a sensitive probe for physics beyond the Standard Model. We have a careful look at the determination of the Unitarity Triangle apex, which is needed for the Standard Model…