Related papers: Composite Dirac Neutrinos
Dirac neutrinos arising from gauged discrete symmetry \`a la Krauss-Wilczek are implemented in the minimal custodial Randall-Sundrum model. In the case of a normal hierarchy, all lepton masses and mixing pattern can be naturally reproduced…
Models with composite singlet neutrinos can give small Majorana or Dirac masses to the active neutrinos. The mechanism is based on the fact that conserved chiral symmetries give massless neutrinos at the renormalizable level. Thus, they…
In this paper, we put forward a connection between the self-interacting dark matter and the Dirac nature of neutrinos. Our exploration involves a $Z_4 \otimes Z_4'$ discrete symmetry, wherein the Dirac neutrino mass is produced through a…
We study neutrino mass generation and dark matter in a left-right symmetric model. The model is based on an $SU(3)_c\times SU(2)_L \times SU(2)_R \times U(1)_{B-L}$ gauge theory with a softly broken parity symmetry. Masses of the charged…
We consider a chiral gauge theory from which light composite Dirac neutrinos dynamically emerge, augmented by a QCD axion to solve the strong CP problem. We show that an interplay between the composite sector and the axion can also…
A new solution is presented where the right-handed neutrino $\nu_R$ in $SO(10)$ pairs up with $\nu_L$ to form a naturally light Dirac neutrino. It is based on the framework of $E_6 \to SO(10) \times U(1)_\psi$, then $SO(10) \to SU(5) \times…
The Dirac masses of neutrinos can exhibit a strong hierarchy even if the Majorana masses of the right-handed neutrinos are degenerate and the hierarchy of the mass scales governing the oscillations of solar and atmospheric neutrinos is…
We analyze signals in the Cosmic Microwave Background (CMB) in theories where the small Dirac neutrino masses arise as a consequence of the compositeness of right-handed neutrinos. In such theories, the right-handed neutrinos are massless…
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…
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…
Amid the uncertainty regarding the fundamental nature of neutrinos, we adhere to the Dirac description, and construct a model in the framework of $\Delta(27)$ symmetry. The model successfully accounts for the hierarchical patterns of both…
We propose a new gauged $B-L$ extension of the standard model where light neutrinos are of Dirac type, naturally acquiring sub-eV mass after electroweak symmetry breaking, without any additional global symmetries. This is realised by…
We present a class of left-right symmetric models where Dirac as well as Majorana mass terms of neutrinos can arise at one-loop level in a scotogenic fashion: with dark matter particles going inside the loop. We show the possibility of…
We implement Dirac neutrinos in the minimal custodial Randall-Sundrum setting via the Krauss-Wilczek mechanism. We demonstrate by giving explicit lepton mass matrices that with neutrinos in the normal hierarchy, lepton mass and mixing…
The nature of neutrinos, whether Dirac or Majorana, is hitherto not known. Assuming that the neutrinos are Dirac, which needs $B-L$ to be an exact symmetry, we make an attempt to explain the observed proportionality between the relic…
We provide a generic framework to obtain stable dark matter along with naturally small Dirac neutrino masses generated at the loop level. This is achieved through the spontaneous breaking of the global $U(1)_{B-L}$ symmetry already present…
A known mechanism for obtaining naturally light Dirac neutrinos is implemented in the context of $SU(6) \to SU(5) \times U(1)_N$.
An extension of the Standard Model (SM) is studied in which two right-handed (RH) neutrinos per generation are incorporated, but considering the hypothesis of the symmetry of lepton and quark contents in order to deprive the number of RH…
Sterile neutrino is a promising dark matter (DM) candidate. However the parameter space of this scenario has almost been ruled out by the X-ray observation results whenever the sterile neutrino is solely produced by the Dodelson-Widrow (DW)…
We discuss how Dirac neutrinos can naturally be generated in supersymmetry and how they allow for an Affleck-Dine leptogenesis scenario, in which a left-right asymmetry is generated in the sneutrino sector, the left part of which is…