Related papers: Two-loop Dirac neutrino mass and WIMP dark matter
The Peccei-Quinn (PQ) mechanism not only acts as an explanation for the absence of strong CP violation but also can play a main role in the solution to other open questions in particle physics and cosmology. Here we consider a model that…
We propose a simple framework to split neutrinos with a slight departure from tribimaximal mixing - where two of the neutrinos are Majorana type which provide thermal leptogenesis. The Dirac neutrino with a tiny Yukawa coupling explains…
We examine simple extension of the standard model with a pair of fermions, one singlet and a doublet, in a common thread linking the dark matter problem with the smallness of neutrino masses associated with several exciting features. In the…
We propose a scotogenic model for generating neutrino masses through a three-loop seesaw. It is a minimally extended inert doublet model with a spontaneously broken global symmetry $U(1)'$ and a preserved $\mathbb{Z}_2$ symmetry. The…
We consider the possibility that Dirac neutrino masses may be a manifestation of chiral symmetry breaking via non-perturbative QCD dynamics. The key role played by light quarks in this mechanism can naturally lead to signals that are…
We construct the one-loop and two-loop scotogenic models for Dirac neutrino mass generation in the context of $U(1)_{B-L}$ extensions of standard model. It is indicated that the total number of intermediate fermion singlets is uniquely…
In this work, we make a detailed discussion on the phenomenology of the scotogenic Dirac model, which could accommodate the Dirac neutrino mass and dark matter. We have studied the LFV processes in this model, which are mediated by the…
We propose a gauge-symmetry origin of a rank-two Dirac neutrino mass matrix that enforces one exactly massless neutrino, while being consistent with the oscillation data, as well as cosmological constraints. The mechanism relies on a…
The origin of neutrino mass and the nature of dark matter (DM) remain unresolved puzzles in particle physics, and an appealing possibility is to address both in a unified picture. This paper explores a light fermionic DM candidate within…
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…
Two Higgs doublets respect a mirror symmetry with spontaneous violation so that their vacuum expectation values can realize a small difference. Under this symmetry, three newly introduced right-handed neutrinos rather than the standard…
In the Dynamical Scotogenic Model, the global $B-L$ symmetry is supposed to be broken spontaneously resulting in a massless Goldstone boson called majoron, and massive right handed neutrinos which participate in the generation of light…
The large hierarchy between the neutrino mass scale and that of the other fermions seems to be unnatural from a theoretical point of view. Various strategies have been devised in order to generate naturally small values of neutrino masses.…
We propose a neutrinophilic two Higgs doublet model with hidden local $U(1)$ symmetry, where active neutrinos are Dirac type, and a fermionic DM candidate is naturally induced as a result of remnant symmetry even after the spontaneous…
In this work, we propose minimal realizations for generating Dirac neutrino masses in the context of a right-handed abelian gauge extension of the Standard Model. Utilizing only $U(1)_R$ symmetry, we address and analyze the possibilities of…
We entertain the possibility that neutrino masses and dark matter (DM) originate from a common composite dark sector. A minimal effective theory can be constructed based on a dark $SU(3)_D$ interaction with three flavors of massless dark…
We propose a Two-Loop induced radiative neutrino model with hidden gauged $U(1)$ symmetry, in which a dark matter of Dirac fermion arises. The relic density gets contribution from annihilation and semi-annihilation due to a residual…
We explain the electron-positron excess reported by the DAMPE collaboration recently in a radiative Dirac seesaw model where a dark $U(1)_X$ gauge symmetry can (i) forbid the tree-level Yukawa couplings of three right-handed neutrinos to…
We show that the neutrino mass generation and the dark matter stability can be governed by the center of the QCD group, which is a $Z_3$ group. Three right-handed neutrinos $N_{1,2,3R}$ transform under $Z_3$ as $1,w,w^2$, where…
We perform a systematic study of the Dirac neutrino masses which arise from a dimension five effective operator with a singlet scalar. We identify all possible realizations of this operator at tree level and one-loop level. The…