Related papers: SU(3) Breaking and D0-D0bar Mixing
In models inspired by non-commutative geometry, patterns of gauge symmetry breaking are analyzed, and SU(5) models are found to naturally favor a vacuum preserving SU(3) X SU(2) X U(1). A more realistic model is presented, and the…
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…
We provide a comprehensive, up-to-date analysis of possible New Physics contributions to the mass difference $\Delta M_D$ in $D^0$-${\bar D}^0$ mixing. We consider the most general low energy effective Hamiltonian and include leading order…
We study the magnitudes of soft SUSY breaking parameters in heterotic string models with anomalous U(1) symmetry. In most cases, D-term contribution to soft scalar masses is expected to be comparable to or dominant over other contributions…
The minimal supersymmetric SO(10) model, in which not only the gauge but also the third generation fermion Yukawa couplings are unified, provides a simple and highly predictive theoretical scenario for the understanding of the origin of the…
SU(3) collective coordinate quantization to the regular solution of the B=2 axially symmetric Einstein-Skyrme system is performed. For the symmetry breaking term, a perturbative treatment as well as the exact diagonalization method called…
Assuming the ${\bar D}^0, D^-, D^-_s$ and $B^+, B^0, B_s^0$ mesons belong to triplets of SU(3) flavor symmetry, we analyse the form factors in the semileptonic decays of these mesons. Both quark and meson mass differences are taken into…
Recently the CDF Collaboration has announced a new precise measurement of the $W$-boson mass $M_W$ that deviates from the Standard Model (SM) prediction by $7\sigma$. The discrepancy in $M_W$ is about $\Delta_W\simeq70$ MeV and probably…
We reexamine the mass mixing and CP violation in the B\bar{B} system in general SU(2)_L \times SU(2)_R \times U(1) models related to the recent measurements. The right-handed contributions can be sizable in B\bar{B} mixing and CP asymmetry…
We analyze a contribution of the finite-width (mass-smearing) effects to the mixing of neutral mesons. It was shown, that this contribution is dominant in the D-meson system and large in the K-meson one. An account of the mass-smearing…
A model of gauge-mediated supersymmetry breaking is constructed in which the low-energy physics depends on a single dynamical scale. Strong coupling dynamics of gauge theories plays an important role, in particular through its effects on…
We show using a model independent approach that the deviation in measured B_d^0-\bar{B}_d^0 mixing phase caused by pollution from another amplitude, within the Standard Model, is always less in magnitude, and has the same sign as the weak…
Intersecting D-brane models in string theory can naturally support the gauge and matter content of left-right symmetric extensions of the Standard Model with gauge symmetry SU(3)_c x SU(2)_L x SU(2)_R x U(1)_{B-L}. Considering such models…
We examine the impact of D-Dbar mixing in the extraction of the angle gamma of the unitarity triangle with B- ->D(*)K(*)- and B- ->D(*)pi- decays. We point out that the leading corrections, linear in the small mixing parameters x=Delta…
The coupling constants $g_L$ and $g_X$ of some versions of the $SU(3)_L\otimes U(1)_X$ extension of the standard model are related through to relationship $g^2_X/g^2_L= \sin^2\theta_W/(1 - 4\sin^2\theta_W)$. This fact suggest that the…
We determine the $SU(3)$-breaking effects in the $\bar{B}/D \rar Kl\bar \nu$ decays from the ratio of the $\bar{B}/D\rar Kl\bar \nu$ over the $\bar{B}/D \rar \pi l\bar \nu$ semileptonic form factors using a {\it semi-analytic} expression…
The most general Lagrangian for a model with two U(1) gauge symmetries contains a renormalizable operator which mixes their gauge kinetic terms. Such kinetic mixing can be generated at arbitrarily high scales but will not be suppressed by…
Based on a nonabelian generalization of electric-magnetic duality, the Dualized Standard Model (DSM) suggests a natural explanation for exactly 3 generations of fermions as the `dual colour' $\widetilde{SU}(3)$ symmetry broken in a…
A new $U(1)_X$ gauge boson $X$ primarily interacting with a dark sector can have renormalizable kinetic mixing with the standard model (SM) $U(1)_Y$ gauge boson $Y$. This mixing besides introduces interactions of dark photon and dark sector…
We investigate a D-brane system in which spontaneous gauge symmetry breaking occurs. The system consists of four D3-branes and three anti-D7-branes at C^3/Z_3 singularity. The singularity is blown up by vacuum expectation values of the…