Related papers: Supersymmetry at the electroweak scale
The LEP2 experiments pose a serious naturalness problem for supersymmetric models. The problem is stronger in gauge mediation than in supergravity models. Particular scenarios, like electroweak baryogenesis or gauge mediation with light…
The possible existence of an exponentially large number of vacua in string theory behooves one to consider possibilities beyond our traditional notions of naturalness. Such an approach to electroweak physics was recently used in "Split…
We study the electroweak phase transition in a supersymmetric version of the Standard Model, in which a gauge singlet superfield is added to the Higgs sector. We show that the order of the transition is determined by the trilinear soft…
We construct a supersymmetric version of the Standard Model which contains a long-lived metastable vacuum. In this vacuum supersymmetry is broken and the electroweak symmetry is Higgsed, and we identify it with the physical ground state of…
The signatures for low energy supersymmetry breaking at the Tevatron are investigated. It is natural that the lightest standard model superpartner is an electroweak neutralino, which decays to an essentially massless Goldstino and photon,…
The electroweak symmetry breaking (EWSB) sector of the Standard Model can be far richer and more interesting than the usual single scalar doublet model. We explore scenarios where the EWSB sector is nearly scale invariant and consequently…
Supersymmetry is a prime candidate for physics beyond the Standard Model because low-energy supersymmetry stabilizes the Higgs mass avoiding fine-tuning and leads to natural electroweak symmetry breaking. However, searches at the Large…
A right-handed stop not much heavier or even lighter than the Z boson has today desirable phenomenological consequences. We study how it can result within the usual radiative scenario of electroweak symmetry breaking. A restriction on the…
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…
We consider an Supersymmetric extension of the Standard Model with some extra Higgs doublets and a global $(B - L)$, where $B$ and $L$ are the usual baryonic and lepton number respectivelly, and ${\cal Z}_{3} \otimes {\cal Z}^{\prime}_{3}$…
We study the baryon asymmetry of the universe in the supersymmetric standard model (SSM). At the electroweak phase transition, the fermionic partners of the charged SU(2) gauge bosons and Higgs bosons are reflected from or transmitted to…
We show that "accidental" supersymmetry is a beyond-the-Standard Model framework that naturally accommodates a thermal relic dark matter candidate and successful electroweak baryogenesis, including the needed strongly first-order character…
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…
A heavy supersymmetric spectrum at the Minimal Supersymmetric Standard Model is considered and the decoupling from the low energy electroweak scale is analyzed. A formal and partial proof of decoupling of supersymmetric particles in the…
Severe constraints on parameters of the minimal supersymmetric standard model follow from a dynamical electroweak symmetry breaking mechanism dominated by top and stop loops. In particular, the lightest Higgs boson mass is expected to be…
The Minimal supersymmetric extension of the Standard Model (MSSM) with light stops, charginos or pseudoscalar Higgs bosons has been suggested as an explanation of the too high value of the branching ratio of the Z0 boson into b quarks (Rb…
Electroweak baryogenesis provides a very attractive scenario to explain the origin of the baryon asymmetry. The mechanism of electroweak baryogenesis makes use of the baryon number anomaly and relies on physics that can be tested…
In the minimal supersymmetric standard model, the conservation of R-parity is phenomenologically desirable, but is ad hoc in the sense that it is not required for the internal consistency of the theory. However, if B-L is gauged at very…
The quantum loop suppressed electroweak processes appear to be very sensitive probes for the symmetry-breaking mechanisms. Since the Standard Model does not involve massive neutrinos, baryon or lepton number violations and the cold dark…
We explore analytically how does the Standard Model emerge as the quantum low energy effective theory of the Minimal Supersymmetric Standard Model (MSSM) in the decoupling limit where the sparticles are much heavier than the electroweak…