Related papers: Coannihilation Effects in Supergravity and D-Brane…
For large values of the minimal supergravity model parameter $\tan\beta$, the tau lepton and the bottom quark Yukawa couplings become large, leading to reduced masses of $\tau$-sleptons and $b$-squarks relative to their first and second…
The 1-loop computation of the processes $\tchi_i \tchi_j \to \gamma Z$ has been performed at an arbitrary c.m. energy for any pair of MSSM neutralinos. As an application suitable for Dark Matter (DM) searches, the neutralino-neutralino…
The thermal relic abundance of species critically depends on the assumed underlying cosmological model. In the case of neutralinos, freeze-out takes place long before Big Bang Nucleosynthesis, which provides the strongest constraint on the…
In the frame of an effective MSSM model without gaugino-mass unification at a grand unification (GUT) scale, we set a lower bound on the neutralino mass based on the new WMAP data on $\Omega_{CDM}$. Our lower bound, $m_{\chi} \gsim 6$ GeV,…
We study the amounts of fine-tuning of the parameters of the MSSM with non-universal soft supersymmetry-breaking contributions to the Higgs masses (the NUHM) that would be required for the relic neutralino density to lie within the range…
We examine the neutralino relic density in the presence of a light top squark, such as the one required for the realization of the electroweak baryogenesis mechanism, within the minimal supersymmetric standard model. We show that there are…
While the constrained minimal supersymmetric standard model (CMSSM) with universal gaugino masses, m_{1/2}, scalar masses, m_0, and A-terms, A_0, defined at some high energy scale (usually taken to be the GUT scale) is motivated by general…
We examine the neutralino dark matter phenomenology in supersymmetric scenarios with nonuniversal Higgs masses at the gauge coupling unification scale that can acommodate a light Higgs boson, where the correct relic density is obtained…
We study the light gluino scenario giving special attention to constraints from the masses of the light CP-even neutral Higgs $m_h$, the lightest chargino $m_{\chi^{\pm}_1}$, and the second lightest neutralino $m_{\chi^0_2}$, and from the…
In supersymmetric models with a long-lived stau being the lightest Standard Model superpartner, the stau abundance during primordial nucleosynthesis is tightly constrained. Considering the complete set of stau annihilation channels in the…
We perform a comprehensive analysis of the decays of charginos and neutralinos in the Minimal Supersymmetric Standard Model where the neutralino $\chi_1^0$ is assumed to be the lightest supersymmetric particle. We focus, in particular, on…
We study pair annihilations of the neutralino dark matter in the minimal supersymmetric standard model with CP violation. We consider the case that the higgsino mass and the trilinear scalar couplings have CP-violating phases of order…
We examine here the constraints from the amount of relic density of neutralino dark matter and other experiments have on the SUSY parameter space for the mSUGRA model and for models with non-universal soft breaking at the GUT scale. In…
An analysis of the $b \rightarrow s\gamma$ is given in supergravity grand unification using the framework of the radiative breaking of the electro-weak symmetry under three separate sets of constraints:1) neutralino relic density does not…
The radiative decay Z2-> Z1 gamma proceeds at the one-loop level in the MSSM. It can be the dominant decay mode for the second lightest neutralino Z2 in certain regions of parameter space of supersymmetric models, where either a dynamical…
We present comprehensive global fits of supersymmetric (SUSY) models from the Global and Modular Beyond-the-Standard-Model Inference Tool (GAMBIT) collaboration, based on arXiv:1705.07935 and arXiv:1705.07917. We investigate several…
We extend the commonly used mSUGRA framework to allow complex soft terms. We show how these phases can induce large changes of the SUSY threshold corrections to the b quark mass and affect the neutralino relic density predictions of the…
We study and explore the low scale implications of Yukawa unification in the minimal gauge mediated supersymmetry breaking models. We also assume non-zero non-holomorphic terms, with which the YU solutions can be accommodated in the cases…
A survey of the mSUGRA/CMSSM parameter space is presented. The viable regions of the parameter space which satisfy all experimental constraints are identified and discussed. These constraints include a 124-127 GeV mass for the lightest…
We consider the minimal supersymmetric extension of the Standard Model (MSSM) with varying amounts of non-universality in the soft supersymmetry-breaking contributions to the Higgs scalar masses. In addition to the constrained MSSM (CMSSM)…