Related papers: The b--->s{\gamma} constraint in effective supergr…
The existence of a dilaton (or moduli) with gravitational-strength coupling to matter imposes stringent constraints on the allowed energy scale of cosmic strings, $\eta$. In particular, superheavy gauge strings with $\eta \sim 10^{16} GeV$…
We study the little hierarchy between mass parameters in the Higgs sector and other SUSY breaking masses. This type of spectrum can relieve the fine-tuning problem in the MSSM Higgs sector. Our scenario can be realized by superconformal…
The connection between Supergravity and the low-energy world is analyzed. In particular, the soft Supersymmetry-breaking terms arising in Supergravity, the $\mu$ problem and various solutions proposed to solve it are reviewed. The soft…
New data on the anomalous magnetic moment a_mu of the muon together with the b->s gamma decay rate are considered within the supergravity inspired constrained minimal supersymmetric model. We perform a global statistical chi^2 analysis of…
The Minimal superstring unification, assuming orbifold compactification, provides interesting and rather detailed implications on physics at low energy. The interesting feature of this model is that the masses of the spectrum are related…
The upper bond on the branching ratio for $b\to s\gamma$ decays implies a stringent lower bound on the mass of the pseudoscalar Higgs boson of the MSSM if sparticles are heavy. This leads to an upper bound on the expected event rate in…
The rare decay $b \to s \gamma$ is studied in the left-right supersymmetric model. We give explicit expressions for all the amplitudes associated with the supersymmetric contributions coming from gluinos, charginos and neutralinos in the…
In left-right symmetric models, large contributions to the decay amplitude $b \rightarrow s+ \gamma$ can arise from the mixing of the $W_L$ and $W_R$ gauge bosons as well as from the charged Higgs boson. These amplitudes are enhanced by the…
To embed the seesaw mechanism in the MSSM, two or three right-handed neutrino supermultiplets, $N_i$, have to be added to the model. In the presence of these new superfields, the soft supersymmetry breaking potential includes a lepton…
In this article, we show that making global fits of string theory model parameters to data is an interesting mechanism for probing, mapping and forecasting connections of the theory to real world physics. We considered a large volume…
The CMS and the ATLAS Collaborations have recently reported on the search for supersymmetry with 35 pb$^{-1}$ of data and have put independent limits on the parameter space of the supergravity unified model with universal boundary…
Supersymmetric (SUSY) theories are often thought to give large branching ratios for $b \rightarrow s \gamma$ from charged Higgs loops. We show that in many cases chargino loop contributions can cancel those of the Higgs, and SUSY can give…
The recent observation by the CLEO Collaboration of the inclusive decay $b\to s\gamma$ with a branching fraction consistent with the expectations of the Standard Model is used to constrain the parameter space of the Left-Right Symmetric…
It has been speculated in the literature that the effective actions of string theories at any order of $\alpha'$ should be invariant under the Buscher rules plus their higher covariant derivative corrections. This may be used as a…
In this work, we investigate the parameter space of the Georgi-Machacek (GM) model, where we consider many theoretical and experimental constraints such as the perturbativity, vacuum stability, unitarity, electroweak precision tests, the…
Many string constructions have a classical no-scale structure, resulting in a one-parameter model (OPM) for the supersymmetry breaking soft terms. As a highly constrained subset of mSUGRA, the OPM has the potential to be predictive.…
In this paper we explore the constraints from B-physics observables in SUSY models of Minimal Flavor Violation, in the large tan beta regime, for both low and high scale supersymmetry breaking scenarios. We find that the rare B-decays b ->…
A review of the soft supersymmetry-breaking parameters and the $\mu$ term arising in superstring models is performed paying special attention to their phenomenological implications. In particular, the violation of the scalar mass…
We provide a study of the phenomenology of heterotic orbifold compactifications scenarii within the context of supergravity effective theories. Our investigation focuses on those models where the soft Lagrangian is dominated by loop…
The recent experimental hints for a relatively heavy Higgs with a mass in the range 119-125 GeV favour supersymmetric scenarios with a large mixing in the stop mass matrix. It has been shown that this is possible in the constrained Minimal…