Related papers: Verifiable Associated Processes from Radiative Lep…
Dark matter pair production at high energy colliders may leave observable signatures in the energy and momentum spectra of the objects recoiling against the dark matter. We use LEP data on mono-photon events with large missing energy to…
We consider a model of neutrino mass with a scalar triplet $(\xi^{++},\xi^+,\xi^0)$ assigned lepton number $L=0$, so that the tree-level Yukawa coupling $\xi^0 \nu_i \nu_j$ is not allowed. It is generated instead through the interaction of…
We study a class of simplified dark matter models in which dark matter couples directly with a mediator and a charged lepton. This class of Lepton Portal dark matter models has very rich phenomenology: it has loop generated dark matter…
We derive model-independent constraints on Higgs mass and couplings from associated signals for higher masses, accessible at LEP2. This work is motivated by the fact that, in many extensions of the standard model, the Higgs boson can have…
Leptogenesis may be induced by the mixing of extra Higgs doublets with experimentally accessible masses. This mechanism relies on diagrammatic cuts that are kinematically forbidden in the vacuum but contribute at finite temperature. A…
We review scenarios in which the particles that account for the Dark Matter (DM) in the Universe interact only through their couplings with the Higgs sector of the theory, the so-called Higgs-portal models. In a first step, we use a general…
Mirror Twin Higgs(MTH) models always contain heavy gauge bosons and extra Higgses. Besides, to accommodate tiny neutrino masses via seesaw mechanism, new heavy neutrinos can also be introduced in MTH extension models. Such new particles and…
It is known that the charged lepton masses obey to high precision an interesting empirical relation (Koide relation). In turn, the light neutrino masses cannot obey such a relation. We note that if neutrinos acquire their mass via the…
In the present universe visible and dark matter contribute comparable energy density although they have different properties. This coincidence can be elegantly explained if the dark matter relic density, originating from a dark matter…
In this work we study the production of a dark matter (DM) particle in association with a Higgs boson via a central exclusive photon-fusion initiated process. We explore this type of production through the Inert Doublet Model plus a complex…
We propose an interesting model of neutrino masses to realize leptogenesis and dark matter at the TeV scale. A real scalar is introduced to naturally realize the Majorana masses of the right-handed neutrinos. We also include a new Higgs…
In this work we study a classically scale invariant extension of the Standard Model that can explain simultaneously dark matter and the baryon asymmetry in the universe. In our set-up we introduce a dark sector, namely a non-Abelian SU(2)…
We study an effective theory beyond the standard model (SM) where either of two additional gauge singlets, a Majorana fermion and a real scalar, constitutes all or some fraction of dark matter. In particular, we focus on the masses of the…
General consequences of mass mixing between the ordinary Z boson and a relatively light Z_d boson, the "dark" Z, arising from a U(1)_d gauge symmetry, associated with a hidden sector such as dark matter, are examined. New effects beyond…
The exo-Higgs model can accommodate a successful baryogenesis mechanism that closely mirrors electroweak baryogenesis in the Standard Model, but avoids its shortcomings. We extend the exo-Higgs model by the addition of a singlet complex…
We consider the Singlet Majorana fermion dark matter model, in which the standard model particles interact with the dark sector through the mixing of a singlet scalar and the Higgs boson. In this model both the dark matter and the singlet…
Dark matter (DM) without a matter asymmetry is studied in the context of Twin Higgs (TH) theories in which the LHC naturalness problem is addressed. These possess a twin sector related to the Standard Model (SM) by a (broken) $\mathbb{Z}_2$…
We study the influence of leptophilic dark matter interactions on decays of muons and ground state mesons in existing experiments. We consider a secluded dark sector exclusively interacting with leptons via either a (leptophilic) scalar or…
The discovery of the Higgs boson suggests that also neutrinos get their mass from spontaneous symmetry breaking. In the simplest ungauged lepton number scheme, the Standard Model (SM) Higgs has now two other partners: a massive CP-even, as…
String effective theories contain a dilaton scalar field which couples to gravity, matter and radiation. In general, particle masses will have different dilaton couplings. We can always choose a conformal frame in which baryons have…