Related papers: $b\to s\gamma$ and $\epsilon_1$ Constraints on Sup…
We present constraints on the extended Starobinsky and Weyl gravity model of inflation using updated available observational data. The data includes cosmic microwave background (CMB) anisotropy measurements from Planck and BICEP/Keck 2018…
We perform a model-independent analysis of top-philic New Physics scenarios, under the assumption that only effective operators involving top quarks are generated at tree level. Within the SMEFT framework, we derive indirect constraints on…
We study flavor violation in a supersymmetric SU(5) grand unification scenario in a model-independent way employing mass insertions. We examine how the quark and the lepton sector observables restrict sfermion mixings. With a low soft…
I review the theoretical expectactions for the top-quark mass in a variety of models: the Standard Model, unified models (GUTs), low-energy supersymmetric models (SUSY), unified supersymmetric models (SUSY GUTs), supergravity models, and…
In the framework of SU(3) symmetry, we present a general analysis of $B$ meson decays into two lighter uncharmed mesons (both pairs of pseudoscalar mesons and pairs of vector and pseudoscalar mesons). From the analysis we find constraints…
We present a measurement of the top-quark mass in $p\bar p$ collisions at \hbox{$\sqrt{s}=1.96$} TeV which uses events with an inclusive signature of missing transverse energy and jets. % The event selection is sensitive to $t\bar t\to…
We introduce an anomalous top quark coupling (right-handed current) into Standard Model Lagrangian. Based on this, a more complete calculation of $b \to s\gamma $ decay including leading log QCD corrections from $m_{top}$ to $M_W$ in…
This note presents constraints on Standard Model parameters using published and preliminary precision electroweak results measured at the electron-positron colliders LEP and SLC. The results are compared with precise electroweak…
The upper bounds that the LHC measurements searching for heavy resonances beyond the Standard model set on the resonance production cross sections are not universal. They depend on various characteristics of the resonance under…
The presence of a light b-squark (with mass about 4 GeV) and gluino (with mass about 15 GeV) might explain the observed excess in b-quark production at the Tevatron. Though provocative, this model is not excluded by present data. The light…
We estimate the top quark, lightest sparticle (LSP) and scalar higgs masses within a supersymmetric grand unified framework in which $\tan\beta \simeq m_t/m_b$ and the electroweak symmetry is radiatively broken. The requirement that the…
The Standard Model of particle physics contains about two dozen parameters - such as particle masses - whose origins are still unknown and cannot be predicted, but whose values are constrained through their interactions. In particular, the…
In some supergravity models, the superlight gravitino is accompanied by a light weakly coupled scalar (S) and pseudo-scalar (P) particle. The coupling of these particles to matter is inversely proportional to the product of the gravitino…
Within the Constrained Minimal Supersymmetric Standard Model (CMSSM) it is possible to predict the low energy gauge couplings and masses of the 3.generation particles from a few parameters at the GUT scale, and electroweak symmetry…
Analysis of the SUSY spectrum in supergravity unified models is given under the naturalness criterion that the universal scalar mass $(m_0)$ and the gluino mass $(m_{\tilde g})$ satisfy the constraint $m_0, m_{\tilde g}$ less than or equal…
We constrain $f(R)$ and chameleon-type modified gravity in the framework of the Berstchinger-Zukin parametrization using the recent released Planck data, including both CMB temperature power spectrum and lensing potential power spectrum.…
We study the flavor physics in two extensions of the quark sector of the Standard Model (SM): a four generation model and a model with a single vector--like down--type quark (VDQ). In our analysis we take into account the experimental…
We present the results of a search for supersymmetry with gauge-mediated breaking and $\NONE\to\gamma\Gravitino$ in the $\gamma\gamma$+missing transverse energy final state. In 2.6$\pm$0.2 \invfb of $p{\bar p}$ collisions at…
Precision measurements of $Z$-boson parameters and $W$-boson and $t$-quark masses put strong constraints on non $SU(2)\times U(1)$ singlet New Physics. We demonstrate that one extra generation passes electroweak constraints even when all…
We consider the branching ratio of $b \to s\gamma$ in gauge mediated supersymmetry breaking theories. Useful bounds on the parameter space of these models are derived from the experimental bounds on $b \to s\gamma$. Constraints on masses of…