Related papers: R_b in Supergravity Grand Unification with Non-uni…
General formulae for the soft SUSY breaking terms, valid in any SUGRA context, were derived in the mid-nineties. Since SUSY is not expected to have quantum anomalies, they should be valid in the quantum theory and be RG invariant down to…
We perform a complete analysis of the supersymmetric particle spectrum in the Minimal Supergravity (mSUGRA) model where the soft SUSY breaking scalar masses, gaugino masses and trilinear couplings are unified at the GUT scale, so that the…
We present an analysis of the discovery reach for supersymmetric particles at the upgraded Tevatron collider, assuming that SUSY breaking results in universal soft breaking parameters at the grand unification scale, and that the lightest…
The general SUSY soft breaking terms for a large class of phenomenologically relevant string scenarios (symmetric orbifolds) are given. They show a certain lack of universality, but not dangerous for flavor changing neutral currents. To get…
We analyse the direct detection of neutralino dark matter in supergravity scenarios with non-universal soft scalar and gaugino masses. In particular, the neutralino-nucleon cross section is computed and compared with the sensitivity of…
Supersymmetric (SUSY) grand unified theories (GUTs) appear to be best motivated for understanding strong, weak and electromagnetic interactions of nature. We briefly review emergence of new formulas for running fermion masses valid in…
We discuss spontaneous supersymmetry (SUSY) breaking in a model with an anomalous $U(1)_A$ symmetry. In this model, the size of the each term in the superpotential is controlled by the $U(1)_A$ charge assignment and SUSY is spontaneously…
Supersymmetry (SUSY) has many well known attractions, especially in the context of Grand Unified Theories (GUTs). SUSY stabilizes scalar mass corrections (the hierarchy problem), greatly reduces the number of free parameters, facilitates…
We discuss the parameter spaces of supersymmetry (SUSY) scenarios taking into account the improved Higgs-mass prediction provided by FeynHiggs 2.14.1. Among other improvements, this prediction incorporates three-loop renormalization-group…
In this talk we discuss SO(10) Yukawa unification and its ramifications for phenomenology. The initial constraints come from fitting the top, bottom and tau masses, requiring large $\tan\beta \sim 50$ and particular values for soft SUSY…
We present a self-consistent $\chi^2$ analysis of several supersymmetric (SUSY) grand unified theories recently discussed in the literature. We obtain global fits to low energy data, including gauge couplings, fermion masses and mixing…
We re-examine the possible magnitude of the supersymmetric contribution to $R_b\equiv\Gamma(Z^0\to\bar b b)/\Gamma(Z^0\to{\rm all})$ in the light of the constraints imposed by the absence of light charginos at LEP~1.5, implementing also…
The effects of nonuniversality of gaugino masses on dark matter are examined within supersymmetric grand unification, and in string and D brane models with R parity invariance. In SU(5) unified models nonuniversality in the gaugino sector…
Indirect information about the possible scale of supersymmetry (SUSY) breaking is provided by B-physics observables (BPO) as well as electroweak precision observables (EWPO). We combine the constraints imposed by recent measurements of the…
We study the correlation of quantum effects on the ratios R_b and R_c within the framework of the MSSM. While in the SM the quantity R_b is in discrepancy with experiment at the 2 \sigma level from below, and R_c differs from the…
I discuss non-trivial effects in the soft SUSY breaking terms which appear when one integrates out heavy fields. The effects exist only when the SUSY breaking terms are non-universal. They may spoil (1) the hierarchy between the weak and…
We obtain general analytical forms for the solutions of the one-loop renormalization group equations in the top/bottom/$\tau$ sector of the MSSM. These solutions are valid for any value of $\tan \beta$ as well as any non-universal initial…
I consider models with non-universal gaugino masses at the gauge coupling unification scale, taking into account the Higgs boson discovery. Viable regions of parameter space are mapped and studied in the case of non-universality following…
We present a SUSY breaking scenario based on Abelian gaugino kinetic term mixings between hidden and observable sectors. If an extra U(1) gaugino in the observable sector obtains a large mass through this mixing effect based on SUSY…
For a long time, the minimal supersymmetric standard model (MSSM) with light masses for the supersymmetric states was considered as the most natural extension of the Standard Model of particle physics. Consequently, a valid approximation…