Related papers: Pseudo-Majoron as Dark Matter
We studied models of leptogenesis where three right-handed Majorana neutrinos are involved and the minimal-extended seesaw mechanism including an additional singlet field produces four light neutrinos. This study shows that the type of mass…
We propose a model to explain tiny masses of neutrinos with the lepton number conservation, where neither too heavy particles beyond the TeV-scale nor tiny coupling constants are required. Assignments of conserving lepton numbers to new…
We review the viability of the sterile neutrino hypothesis in accounting for three observational problems of the Standard Model of particle physics: neutrino masses and lepton mixing, dark matter and the baryon asymmetry of the Universe. We…
We study a minimal extension of the Standard Model where a scalar field is coupled to the right handed neutrino responsible for the see-saw mechanism for neutrino masses. In the absence of other couplings, below 8 TeV the scalar $A$ has a…
The E6 inspired extension of the minimal supersymmetric (SUSY) standard model (MSSM) with an extra U(1)_N gauge symmetry, under which right-handed neutrinos have zero charge, involves exotic matter beyond the MSSM to ensure anomaly…
We explore the range of parameters for dark-matter sterile neutrinos in an extention of the Minimal Standard Model by three singlet fermions with masses below the electroweak scale (the $\nu$MSM). This simple model can explain a wide range…
We investigate a dark matter model involving an inert $\mathrm{SU}(2)_\mathrm{L}$ quadruplet scalar with hypercharge 1/2. After the electroweak symmetry breaking, the dark sector contains one doubly charged, two singly charged, and two…
We discuss the phenomenology of a minimal model for GeV-scale Majorana dark matter (DM) coupled to the standard model lepton sector via a charged scalar singlet. The theoretical framework extends the Standard Model by two $SU(2)_L$…
A mechanism for leptogenesis at the electroweak scale was investigated in a model of dark energy and dark matter proposed by one of us (PQH). This model involves an asymptotically free gauge group SU(2)Z and an axion-like particle with an…
The Majoron is a hypothetical (pseudo) Nambu-Goldstone boson arising from the spontaneous breaking of a global lepton number symmetry, and is known as a candidate for dark matter in our Universe. In this paper, we investigate the…
The seesaw type II mechanism is considered within the framework of a left-right chiral model with a gauge group $SU(2)_L\times SU(2)_R\times U(1)$, the lepton sector of which includes three generations of heavy Majorana neutrinos. The…
We consider a minimal extension of the Standard Model with one singlet neutrino per generation that can realize resonant leptogenesis at the electroweak scale. In particular, the baryon asymmetry in the Universe can be created by resonant…
We suggest that recent neutrino puzzles that are the solar and atmospheric neutrino deficits as well as the possible neutrino oscillations reported by the LSND experiment and the possibility of massive neutrinos providing the hot component…
In the Supersymmetric extension of the Standard Model with minimal particle content the three neutrinos can have non trivial masses and mixings, generated at 1 loop due to renormalizable lepton number violating interactions. We show that…
We study a one-loop induced neutrino mass model with an inert isospin triplet scalar field of $Y=0$ and heavier isospin doublet vector-like leptons and singlet Majorana right-handed fermions. In addition to the neutrino mass matrix, We…
The damping rate and free path of neutrinos in the singlet Majoron model have been calculated including both finite temperature and symmetry breaking effects. The behaviour of right- and left-handed fermions are found inherently different.…
We propose a minimal model for the cosmic coincidence problem $\Omega_{\rm DM}/\Omega_B \sim 5$ and neutrino mass in a type-II seesaw scenario. We extend the standard model of particle physics with a $\rm SU(2)$ singlet leptonic Dirac…
We discuss asymmetric or symmetric dark matter candidate in the supersymmetric Dirac leptogenesis scenario. By introducing a singlet superfield coupling to right-handed neutrinos, the overabundance problem of dark matter can be evaded and…
We discuss singlet fermion dark matter within a left-right symmetric model promoting baryon and lepton numbers as separate gauge symmetries. We add a simple Dirac fermionic dark matter singlet under $SU(2)_{L,R}$ with nonzero and equal…
The most promising scenarios of baryogenesis seems to be the one through lepton number violation. Lepton number violation through a Majarana mass of the right-handed neutrinos can generate a lepton asymmetry of the universe when the…