Related papers: Renormalization Group Study of the Minimal Supersy…
The minimal supersymmetric standard model, and extensions, have stringent upper bounds on the mass of the lightest Higgs boson if perturbativity up to the Planck scale is assumed. We argue that these bounds are softened tremendously if the…
We construct supersymmetric theories in which the correct scale for electroweak symmetry breaking is obtained without significant fine-tuning. We calculate the fine-tuning parameter for these theories to be at the 20% level, which is…
In supersymmetric models with minimal particle content and without large left-right squarks mixing, the conventional knowledge is that the Higgs Boson mass around 125 GeV leads to top squark masses ${\cal O}(10)$ TeV, far beyond the reach…
While it is often stated that the notion of electroweak (EW) naturalness in supersymmetric models is subjective, fuzzy and model-dependent, here we argue the contrary: electroweak naturalness can be elevated to a {\it principle} which is…
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 study models in which supersymmetry breaking appears at an intermediate scale, M_in, below the GUT scale. That is, that the soft supersymmetry-breaking parameters of the MSSM are universal at M_in. We demand that the lightest neutralino…
We consider the supersymmetric extension of the standard model with an additional singlet $S$, the Non-Minimal Supersymmetric Standard Model (NMSSM), in the limit $\tan\beta \simeq m_t/m_b$. We embed this model in a supergravity framework…
We present semi-analytical solutions of the supersymmetric non-universal masses models for low $\tan\beta$ regime. In addition to this, scale and $\tan\beta$ dependencies of the soft (mass)$^2$ terms are given in the form of numerical…
We analyze some features of the role that extra dimensions, of radius $R$ in the TeV$^{-1}$ range, can play in the soft breaking of supersymmetry and the spontaneous breaking of electroweak symmetry. We use a minimal model where the gauge…
A model of gauge-mediated supersymmetry breaking is constructed in which the low-energy physics depends on a single dynamical scale. Strong coupling dynamics of gauge theories plays an important role, in particular through its effects on…
We study the next-to-minimal supersymmetric standard model. We consider soft supersymmetry breaking parameters, which are induced by the mirage mediation mechanism of supersymmetry breaking. We concentrate on the mirage mediation, where the…
The Next-to-Minimal Supersymmetric Standard Model (NMSSM) provides a natural framework to realize a low-scale supersymmetric (SUSY) model, where a singlet superfield is added to the minimal model to generate a SUSY-scale higgsino mass term…
Vacuum stability implies a lower limit on the mass of the higgs boson in the Standard Model (SM). In contrast, an upper limit on the lightest higgs mass can be calculated in supersymmetric (susy) models. The main uncertainty in each limit…
It is shown that the minimal supersymmetric SO(10) model with electroweak radiative breaking and universal soft mass terms at the GUT scale is strongly disfavoured by the combination of constraints from the $b\to s \gamma$ decay and the…
It is studied that `no-scale' model makes hierarchy between scalar top mass and Z boson mass naturally. The supersymmetry breaking parameters are constrained by flavor changing neutral currents in minimal supersymmetric standard model. One…
We propose a new realization of softly broken supersymmetric theories as theories defined on stochastic superspace. At the classical level, the supersymmetry breaking is parameterized in terms of a single (in general complex) mass…
The electroweak (EW) symmetry breaking in the simplest supersymmetric (SUSY) extensions of the standard model (SM), i.e. minimal and next-to-minimal supersymmetric standard models (MSSM and NMSSM), is considered. The spectrum of the Higgs…
Vacuum stability and metastability imply lower limits on the mass of the higgs boson in the Standard Model (SM). In contrast, we present an improved calculation of an upper limit on the lightest higgs mass in supersymmetric (susy) models,…
We explore the phenomenological predictions of a supersymmetric standard model, with a large extra dimension and unifying gauge couplings. The modified five dimensional renormalisation group equations make it possible to obtain light,…
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…