Related papers: A model of light pseudoscalar dark matter
We investigate the Standard Model (SM) with a $U(1)_{B-L}$ gauge extension where a $B-L$ charged scalar is a viable dark matter (DM) candidate. The dominant annihilation process, for the DM particle is through the $B-L$ symmetry breaking…
We investigate the phenomenology of an extension of the Standard Model (SM) by a non-abelian gauge group $SU(2)_{HS}$ where all SM particles are singlets under this gauge group, and a new scalar representation $\phi$ that is singlet under…
The seesaw and leptogenesis commonly depend on the masses of same particles, and thus are both realized at the same scale. In this work, we demonstrate a new possibility to realize a TeV-scale neutrino seesaw and a natural high-scale…
We explore scalar dark matter that is part of a lepton flavor triplet satisfying symmetry requirements under the hypothesis of minimal flavor violation. Beyond the standard model, the theory contains in addition three right-handed neutrinos…
In this work, we present UV completions of the recently proposed number-changing Co-SIMP freeze-out mechanism. In contrast to the standard cannibalistic-type dark matter picture that occurs entirely in the dark sector, the $3\to 2$ process…
Alternatives to the see-saw mechanism are explored in supersymmetric models with three right-handed or sterile neutrinos. Tree-level Yukawa couplings can be drastically suppressed in a natural way to give sub-eV Dirac neutrino masses. If,…
We consider a simple extension of the Standard Model providing dark matter and a TeV-scale seesaw mechanism that also allows for viable leptogenesis. In addition to the Standard Model degrees of freedom, the model contains a neutrinophilic…
Dark matter (DM) could be a relic of freeze-in through a light mediator, where the DM is produced by extremely feeble, IR-dominated processes in the thermal Standard Model plasma. In the simplest viable models with the DM mass below the MeV…
In an endeavor to explain the light neutrino masses and dark matter (DM) simultaneously, we study a gauged $U(1)_{\rm B-L}$ extension of the standard model (SM). The neutrino masses are generated through a variant of type-II seesaw…
An electroweak (EW) sector of the Minimal Supersymmetric Standard Model (MSSM) with masses of a few hundred GeV can account for variety of experimental data, assuming the lightest neutralino to be the lightest supersymmetric (SUSY)…
We propose an extra $U(1)_X$ model with an alternative charge assignment for right-handed right-handed neutrinos. The type-II seesaw mechanism by a triplet Higgs field is promising for neutrino mass generation because of the alternative…
It has been pointed out in ref.[1] that in the nuMSM (Standard Model extended by three right-handed neutrinos with masses smaller than the electroweak scale), there is a corner in the parameter space where CP-violating resonant oscillations…
Next-to-Minimal Supersymmetric Standard Model neutralino dark matter candidates in the (1-15) GeV range are found with a Markov Chain Monte Carlo scanning code. A very light, singlet-like Higgs and/or CP-odd Higgs is needed in order to…
About $26\%$ of the matter in our Universe is made up of Dark Matter (DM), which interacts with Standard Model (SM) matter only through gravitational or weak interactions. Many proposals have been made by scientists about the possible…
Seesaw models with a small lepton number breaking can naturally accommodate electroweak-scale pseudo-Dirac neutrinos with a sizable mixing with the active neutrinos, while satisfying the light neutrino oscillation data. Due to the smallness…
Neutrino masses and light (keV-GeV) sterile neutrinos can arise naturally via a modified, low energy seesaw mechanism if the right-handed neutrinos are charged under a new symmetry broken by a PeV scale vacuum expectation value, presumably…
A solution to the problem of the origin of matter in the universe can be reasonably searched within extensions of the standard model that also explain neutrino masses and mixing. Models embedding the minimal seesaw mechanism can explain the…
We consider a simple extension of the Standard Model with two singlet scalar fields and three heavy right-handed neutrinos. One of the scalar fields serves as an MeV scale dark matter and its stability is ensured by the introduction of an…
We consider minimal $U(1)$ extensions of the Standard Model in which one of the right-handed neutrinos is charged under the new gauge symmetry and plays the role of dark matter. In particular, we perform a detailed phenomenological study…
Our contribution sets out to investigate the phenomenology of a gauge model based on an $SU_{L}(2) \times U_{R}(1)_{J} \times U(1)_{K}$-symmetry group. The model can accommodate in its distinct phases - by virtue of different…