Related papers: Weak-Singlet Fermions: Models and Constraints
We review simplified models in which a singlet Majorana dark matter candidate couples to Standard Model (SM) fermions through interactions mediated by scalar fermion partners. We summarize the two primary production mechanisms in these…
We investigate a minimal extension of the Standard Model with a real singlet scalar and a singlet Dirac fermion acting as dark matter. Unlike a conventional singlet scalar setup, we assume that the singlet scalar does not acquire a vacuum…
The Kaluza-Klein fermion excitations induce mixing between the Standard Model fermions and loss of universality. The flavour mixing not present in the Standard Model can be made to vanish aligning the Yukawa couplings and the Dirac masses…
Using effective field theory approach, we study the constraints from electroweak data on the SU(5)/SO(5), SU(6)/SP(6), SU(3)xU(1) little Higgs models and their variations. We construct an effective theory valid above the electroweak…
Many scenarios of new physics predict the existence of neutrino Non-Standard Interactions, new vector contact interactions between neutrinos and first generation fermions beyond the Standard Model. We obtain model-independent constraints on…
Meson-antimeson mixing provides the most stringent constraints on baryon- and lepton-number conserving New Physics, probing scales higher than $10^5$ TeV. In the context of the effective theory of weak interactions, these constraints…
This note presents constraints on Standard Model parameters using published and preliminary precision electroweak results measured at the electron-positron colliders LEP and SLC. The results are compared with precise electroweak…
Direct searches for WIMPs are sensitive to physics well below the weak scale. In the absence of light mediators, it is fruitful to apply an Effective Field Theory (EFT) approach accounting only for dark matter (DM) interactions with…
Mirror fermions with masses around the weak scale could break dynamically the electroweak symmetry if they were coupled with a new strong interaction. The purpose of this talk is to show what sort of dynamics are needed in order to render…
Studies in nuclear and atomic physics have played an important role in developing our understanding of the Standard Model of electroweak interactions. We review the basic ingredients of the Standard Model, and discuss some key nuclear and…
We review our efforts in investigating gauge theories with fermions in the adjoint representation of the gauge group by means of numerical simulations. These theories have applications in possible extensions of the Standard Model of…
Dark matter models can give rise to specific signatures at particle physics experiments or in cosmology. The details of the cosmological history can also influence the new physics signals to be expected at e.g. collider experiments. In…
We analyze the compatibility of the hypothesis of third-family quark-lepton unification at the TeV scale with electroweak precision data, lepton flavor universality tests, and high-$p_T$ constraints. We work within the framework of the UV…
The study of electron-positron collisions at LEP, together with additional measurements from other experiments, in particular those at SLC and at the Tevatron, has allowed for tests of the electroweak Standard Model with unprecedented…
We explore the possible exotic particle content beyond the standard model by examining all its scalar bilinear combinations. We categorize these exotic scalar fields and show that without the suppression of (A) their Yukawa couplings with…
The Weakly Interacting Massive Particle (WIMP) paradigm is one of the most popular scenarios for Dark Matter (DM) theories that however is strongly constrained, in particular by direct detection experiments. We stick with the WIMP…
With the renewed interest in vector-like fermion extensions of the Standard Model, we present here a study of multiple vector-like theories and their phenomenological implications. Our focus is mostly on minimal flavor conserving theories…
We continue the study of weakly interacting massive particles (WIMP) started in [arXiv:2107.09688], focusing on a single complex electroweak $n$-plet with non-zero hypercharge added to the Standard Model. The minimal splitting between the…
We study constraints on Composite Higgs models with fermion partial compositeness from electroweak precision measurements, including the 2022 $W$-boson mass result from the CDF collaboration. We focus on models where the Composite Higgs…
The introduction of mirror fermions with masses between the weak scale and 1 TeV could offer a dynamical origin to the standard-model electro-weak symmetry breaking mechanism. The purpose of this work is to study the dynamics needed in…