Related papers: Light Dark Sectors through the Fermion Portal
We explore a simple extension to the Standard Model containing two gauge singlets: a Dirac fermion and a real pseudoscalar. In some regions of the parameter space both singlets are stable without the necessity of additional symmetries, then…
Higgs-portal effective field theories are widely used as benchmarks in order to interpret collider and astroparticle searches for dark matter (DM) particles. To assess the validity of these effective models, it is important to confront them…
We introduce a new class of renormalisable models, consisting of a dark $SU(2)_D$ gauge sector connected to the Standard Model (SM) through a Vector-Like (VL) fermion mediator, not requiring a Higgs portal, in which a massive vector boson…
We explore a simple and renormalizable model which incorporates a new stable fermion that accounts for the dark matter in the universe and which, at the same time, provides an interpretation of two recent measurements that deviate from the…
We generalize in several directions our recent analysis of the limitations to the use of the effective field theory approach to study dark matter at the LHC. Firstly, we study the full list of operators connecting fermion DM to quarks and…
Where collider searches for resonant invisible particles loose steam, dark sectors might leave their trace as virtual effects in precision observables. Here we explore this option in the framework of Higgs portal models, where a sector of…
We explore new EFT operators where single new exotic states interact with the Standard Model through an asymmetric Standard Model portal with couplings to at least one quark and one W boson. Effective operators up to dimension 6 are…
A minimal extension of the left-right symmetric model for neutrino masses that includes a vector-like singlet fermion dark matter (DM) is presented with the DM connected to the visible sector via a gauged U(1) portal. We discuss the…
We combine and extend the analyses of effective scalar, vector, Majorana and Dirac fermion Higgs portal models of dark matter (DM), in which DM couples to the Standard Model (SM) Higgs boson via an operator of the form…
We consider a model of dark matter whose most prominent signature is a monochromatic flux of TeV neutrinos from the galactic center. As an example of a general scenario, we consider a specific model where the dark matter is a fermion in the…
We consider an extension of the Standard Model with two right-handed singlet fermions with mass at the electroweak scale that induce neutrino masses, plus a generic new physics sector at a higher scale $\Lambda$. We focus on the effective…
Assuming ({\it i}) the seesaw mechanism works for neutrino masses and mixings, ({\it ii}) dark matter is absolutely stable due to unbroken $U(1)_X$ dark gauge symmetry, and ({\it iii}) the singlet fields ($H^\dagger H$ and $N_R$) are portal…
We present a new class of Dark Matter (DM) models wherein the Standard Model (SM) is extended with a new $SU(2)_D$ dark gauge sector. In this framework the stability of DM is provided by the conservation of a $U(1)$ global symmetry, which…
The aim of this thesis is to determine possible interactions between the Standard Model with right-chiral neutrinos and a sector of dark matter composed of a real scalar, left- and right-chiral fermion and a vector particle, which are…
Dark sectors provide beyond Standard Model scenarios which can address unresolved puzzles, such as the observed dark matter abundance or the baryon asymmetry of the Universe. A naturally small portal to the dark sector is obtained if…
We study an extension of the Standard Model with electroweak scale right-handed singlet fermions $N$ that induces neutrino masses, plus a generic new physics sector at a higher scale $\Lambda$. The latter is parametrized in terms of…
Conventional approaches to describe dark matter phenomenology at collider and (in)direct detection experiments in the form of dark matter effective field theory or simplified models suffer in general from drawbacks regarding validity at…
We re-examine current and future constraints on a heavy dilaton coupled to a simple dark sector consisting of a Majorana fermion or a St\"uckelberg vector field. We include three different treatments of dilaton-Higgs mixing, paying…
We perform a detailed study of an effective field theory which includes the Standard Model particle content extended by a pair of Weyl fermionic SU(2)-doublets with opposite hypercharges. A discrete symmetry guarantees that a linear…
We discuss the sensitivity of neutrino experiments at the luminosity frontier to generic hidden sectors containing new (sub)-GeV neutral states. The weak interaction of these states with the Standard Model can be efficiently probed through…