Related papers: Dirac Neutrino Mass Matrix and its Link to Freeze-…
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…
We examine an extension of the Standard Model that addresses the dark matter puzzle and generates Dirac neutrinos masses through the radiative seesaw mechanism. The new field content includes a scalar field that plays an important role in…
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 present a model that extends the standard model by incorporating the simplest discrete symmetry groups, $Z_2$ and $Z_3$. This model introduces vector-like leptons and a real scalar singlet. Based on this framework, we generate Dirac…
Neutrinos may be the harbingers of new dark sectors, since the renormalizable neutrino portal allows for their interactions with hidden new physics. We propose here to use this fact to connect the generation of neutrino masses to a light…
We revisit the possibility of a Dirac fermion dark matter candidate in the light of current $b \to s \ell^+ \ell^-$ anomalies by investigating a minimal extension of the Standard Model with a horizontal $\mathrm{U(1)}^{\prime}$ local…
In this paper, we explore a dark sector scenario with a gauged $SU(2)_R$ and a global $U(1)_X \times \mathbb{Z}_2$, where the continuous symmetries are spontaneously broken to a global $U(1)_D$. We show that in various regions of the…
In theories with a low quantum gravity scale, global symmetries are expected to be violated, inducing excessive proton decay or large Majorana neutrino masses. The simplest cure is to impose discrete gauge symmetries, which in turn make…
In this thesis I discuss in some detail the possibility that neutrinos are Dirac. If this is indeed the case, some extra symmetries beyond the Standard Model gauge group need to be enforced in order to protect Diracness and the smallness of…
We consider a U(1)' gauge symmetry acting on three generations of right-handed neutrinos. The U(1)' symmetry is broken at the TeV scale and its remnant discrete symmetry makes one of the right-handed neutrinos stable. As a natural…
An effective theory for dark matter has recently been proposed. The key assumption is that the dark matter particle which is a Dirac fermion is protected from decaying by a global U(1) symmetry. We point out that quantum gravity effects…
We show a TeV-scale seesaw model where Majorana neutrino masses, the dark matter mass, and stability of the dark matter can be all originated from the U(1)_{B-L} gauge symmetry. Dirac mass terms for neutrinos are forbidden at the tree level…
We demonstrate that Dirac neutrino masses in the experimentally preferred range are generated within supersymmetric gauge extensions of the Standard Model with a generalized supersymmetry breaking sector. If the usual superpotential Yukawa…
We propose a Dirac neutrino portal dark matter scenario by minimally extending the particle content of the Standard Model (SM) with three right handed neutrinos ($\nu_R$), a Dirac fermion dark matter candidate ($\psi$) and a complex scalar…
We propose an extension of the standard model, in which neutrinos are Dirac particles and their tiny masses originate from a one-loop radiative diagram. The new fields required by the neutrino mass-generation also accommodate the…
We propose the simplest TeV-scale scotogenic extension of the original 3-3-1 theory, where dark matter stability is linked to the Dirac nature of neutrinos, which results from an unbroken $B-L$ gauge symmetry. The new gauge bosons get…
A minimal extension of the Standard Model is proposed, where the observed left-handed neutrinos obtain naturally small Majorana masses from a one-loop radiative seesaw mechanism. This model has two candidates (one bosonic and one fermionic)…
We show that the mu problem and the strong CP problem can be resolved in the context of the gauged U(1)_R symmetry, realizing an automatic Peccei-Quinn symmetry. In this scheme, right-handed neutrinos can be introduced to explain small…
We present a new approach for generating tiny neutrino masses. The Dirac neutrino mass matrix gets contributions from two new Higgs doublets with their vevs at the electroweak (EW) scale. Neutrino masses are tiny not because of tiny Yukawa…
We propose a radiative Dirac neutrino mass model stabilized by a non-invertible fusion rule originating from a $Z_3 \times Z_3'$ gauging. The imposed symmetry forbids tree-level Yukawa couplings and ensures that neutrino masses are…