Related papers: Probing Supergravity Models with Indirect Experime…
We discuss supersymmetric contributions to the electroweak precision measurements in the Minimal Supersymmetric Standard Model for two cases: the quark-lepton universality violation $\delta_{q\ell}$ in charged currents and the ratio…
We update our analysis of precision electroweak measurements using the latest data announced at Moriond, March 1998. Possible oblique corrections from new physics are parametrized using the STU formalism of Ref.[1], and non-oblique…
A quantitative analysis of $\amu\equiv{1\over 2}(g-2)_\mu$ within the framework of Supergravity Grand Unification and radiative breaking of the electro-weak symmetry is given. It is found that $a_{\mu}^{SUSY}$ is dominated by the chiral…
Within the framework of a renormalizable $SU(5)_{L} \times U(1)_{Y}$ electro-weak gauge model with no exotic electric charges, we obtain all the neutral weak charge operators and their quantization, once the diagonalization of the neutral…
A new framework to study electroweak physics at one-loop level in general ${\rm SU(2)_L \times U(1)_Y}$ theories is introduced. It separates the 1-loop corrections into two pieces: process specific ones from vertex and box contributions and…
We evaluate the branching ratio BR($b\rightarrow s,\gamma$) in the minimal supersymmetric standard model (MSSM), determining the corresponding phenomenological restrictions on two attractive supergravity scenarios, namely minimal…
We consider electroweak symmetry breaking in supersymmetric models with an extra non-anomalous U(1)' gauge symmetry and an extra standard-model singlet scalar S. For appropriate charges the U(1)' forbids an elementary mu term, but an…
We discuss several aspects of state-of-the-art calculations of radiative electroweak symmetry breaking in supergravity models. These models have a five-dimensional parameter space in contrast with the 21-dimensional one of the MSSM. We…
Minimal $N=1$ supergravity with a radiatively broken electroweak symmetry group is studied in the light gluino scenario. Constraints from the $b\rightarrow s\gamma$ decay and from the masses of the light CP-even neutral Higgs $m_h$, the…
The quantum loop suppressed electroweak processes appear to be very sensitive probes for the symmetry-breaking mechanisms. Since the Standard Model does not involve massive neutrinos, baryon or lepton number violations and the cold dark…
The electroweak model is formulated on the nonlinearly realized gauge group SU(2) X U(1). This implies that in perturbation theory no Higgs field is present. The paper provides the effective action at the tree level, the Slavnov Taylor…
We make a complete analysis of radiative symmetry breaking in the MSSM and its $SU(5)$ extensions including low- and high-energy threshold effects in the framework of the two-loop renormalization group. In particular, we consider minimal…
A novel approach to study electroweak physics at one-loop level in generic ${\rm SU(2)_L \times U(1)_Y}$ theories is introduced. It separates the 1-loop corrections into two pieces: process specific ones from vertex and box contributions,…
We compute the full set of weak-scale gauge and Yukawa threshold corrections in the minimal supersymmetric standard model, including all finite (non-logarithmic) corrections, which we show to be important. We use our results to examine the…
We present a string-inspired/derived supergravity model based on the flipped $SU(5)\times U(1)$ structure supplemented by a minimal set of additional matter representations such that unification occurs at the string scale…
A series of predictions are worked out in order to put the minimal $SU(5)$ supergravity model under experimental test. Using the two-loop gauge coupling renormalization group equations, with the inclusion of supersymmetric threshold…
The minimal grand unified supergravity model is discussed. Requiring radiative breaking of the electroweak gauge symmetry, the unification of b and tau Yukawa couplings, a sufficiently stable nucleon, and not too large a relic density of…
We evaluate regions of parameter space in the minimal supergravity model where ``unbounded from below'' (UFB) or charge or color breaking minima (CCB) occur. Our analysis includes the most important terms from the 1-loop effective…
In a recent paper, we introduced a new Little Higgs model, which contains the gauge structure $SU(2)^3\times U(1)$, embedded in an approximate global $SO(5)\times SO(5)$ symmetry. After breaking to the standard model, $SU(2)_L \times…
It is analyzed the branching ratio $B(b\rightarrow s\gamma)$ in the context of minimal $N=1$ supergravity with radiatively broken electroweak symmetry group. There is a strong dependence on supersymetric parameters, but constraints on the…