Related papers: Electroweak Precision Measurements and the Minimal…
The most important hint of physics beyond the Standard Model (SM) from the 1995 precision electroweak data is that the most precisely measured quantities, the total, leptonic and hadronic decay widths of the $Z$ and the effective weak…
The supersymmetric one-loop contribution to the quark-lepton universality violation in the low-energy charged current weak interactions is studied. It is shown that the recent experimental data with the 1-$\sigma$ deviation from the…
We study vertex corrections to the leptonic electroweak observables in the general MSSM at tan(beta) < 35. In particular, we address the question of whether supersymmetry can be responsible for the observed 2 sigma deviation from the…
We investigated the electroweak corrections from one-loop diagrams involving the third generation (s)quarks to the decay width of process $\tilde{\chi}_1^+ \to W^+ \tilde{\chi}_1^{0}$ in the framework of the Minimal Supersymmetric Standard…
We systematically analyze the anomalous dipole $\Delta k_{\gamma}$ and quadrupole $\Delta Q_{\gamma}$ moments of the W gauge bosons in the context of the minimal supersymmetric standard model as functions of the soft SUSY breaking…
As experimental constraints on the parameter space of the MSSM and close variations thereof become stronger, the motivation to explore supersymmetric models that challenge some of the standard assumptions of the MSSM also become stronger.…
Electroweak precision measurements can provide indirect information about the possible scale of supersymmetry already at the present level of accuracy. We update the present-day sensitivities of precision data using the new experimental…
We study constraints on the supersymmetric standard model from the updated electroweak precision measurements --- the Z-pole experiments and the $W$-boson mass measurements. The supersymmetric-particle contributions to the universal…
We explore the one-loop electroweak radiative corrections in the minimal $SU(5)$ and the no-scale flipped $SU(5)$ supergravity models via explicit calculation of vacuum polarization contributions to the $\epsilon_{1,2,3}$ parameters.…
We describe non-standard contributions to semileptonic processes in a model independent way in terms of an SU(2)_L X U(1)_Y invariant effective lagrangian at the weak scale, from which we derive the low-energy effective lagrangian governing…
There are two aspects to the 1995 summer update of the combined preliminary electroweak data from LEP and SLC. On the one hand, agreement between experiments and the Standard Model (SM) has improved for the line-shape and the asymmetry…
We study constraints on the Minimal Supersymmetric Standard Model from electroweak experiments. We find that the light sfermions always make the fit worse than the Standard Model, while the light chargino generally make the fit slightly…
The simplest interpretation of the global success of the Standard Model is that new physics decouples well above the electroweak scale. Supersymmetric extension of the Standard Model offers the possibility of light chargino and the…
The present Standard Model fit of precision data has a low confidence level, and is characterized by a few inconsistencies. We look for supersymmetric effects that could improve the agreement among the electroweak precision measurements and…
The main purpose of this thesis is to discuss the impact of electroweak precision measurements on the present knowledge of particle physics, both in the framework of the Standard Model and of its most straightforward extensions. In Chapter…
I discuss the static quantities of the W boson, magnetic dipole and electric quadrupole moments, in the context of the minimal supersymmetric standard model, in which supersymmetry is broken by soft terms $A_o,\, m_o,\, M_{1/2}$. Following…
The Standard Model global fit to precision data is excellent. The Minimal Supersymmetric Standard Model can also fit the data well, though not as well as the Standard Model. At best, supersymmetric contributions either decouple or only…
The dominant electroweak two-loop corrections to the precision observables M_W and s_w^eff are calculated in the MSSM. They are obtained by evaluating the two-loop Yukawa contributions of O(alpha_t^2), O(alpha_t alpha_b), O(alpha_b^2) to…
We address the compatibility of a light sbottom (mass $2\sim 5.5 \gev$) and a light gluino (mass $12\sim 16 \gev$) with electroweak precision measurements. Such light particles have been suggested to explain the observed excess in the $b$…
We present a supersymmetric extension of the Standard Model that posseses a continuous $ U(1)_R$ symmetry, which is identified with one of three lepton numbers, and where a sneutrino vev gives mass to the down type quark and leptons. This…