Related papers: Z_3 Dark Matter and Two-Loop Neutrino Mass
We discuss a simple theory for neutrino masses where the total lepton number is a local gauge symmetry spontaneously broken below the multi-TeV scale. In this context, the neutrino masses are generated through the canonical seesaw mechanism…
The most plausible see-saw explanation of the smallness of the neutrino masses is based on the assumption that total lepton number is violated at a large scale and neutrinos with definite masses are Majorana particles. In this review we…
We study the generation of small neutrino masses from the dimension six effective operator at tree level and one-loop level, the neutrinos are assumed to be Dirac particles. We find out all possible tree and one-loop diagrams which lead to…
A comet-like, but magnitudes smaller, extremely low albedo interstellar meteoroid population of fragile aggregates with solar type composition, measured in space and terrestrially, is most probably the universal dark matter. Although…
Pseudo-Dirac Dark Matter is a viable type of dark matter which originates from a new Dirac fermion whose two Weyl states get slightly split in mass by a small Majorana term. The decay of the heavier to the lighter state naturally occurs…
Partial Split Supersymmetry with bilinear R-parity violation allows to reproduce all neutrino mass and mixing parameters. The viable dark matter candidate in this model is the gravitino. We study the hypothesis that both possibilities are…
Dynamical mass discrepancies in galaxies have two possible explanations: the existence of large amounts of dark matter or the breakdown of Newtonian gravity. True dark matter halos of galaxies could differ in several respects from apparent…
When the singlet-doublet fermion dark matter model is extended with additional $Z_2$--odd real singlet scalars, neutrino masses and mixings can be generated at one-loop level. In this work, we discuss the salient features arising from the…
A simple 3 X 3 neutrino mass matrix is proposed to accommodate both the solar and atmospheric neutrino deficits. This scenario can be realized naturally by a radiative mechanism for the generation of neutrino masses. It also goes together…
We propose a minimal extended seesaw scheme based on the discrete symmetry $A_4\times Z_4\times Z_2\times Z_8$ which can successfully address neutrino phenomenology and keV sterile neutrino dark matter. The lepton mass hierarchy is…
This study presents a radiative three-loop model for neutrino mass generation, employing an asymmetric Yukawa coupling between two new scalar $SU(2)_L$ doublets and vectorlike lepton doublets. Dark matter candidates arise from one of the…
It has recently been proposed that the relatively inert, highly symmetric, neutral flavor singlet scalar hadron made of uuddss quarks may have a mass < 2 (m_p + m_e). This is consistent with QCD theory, and with existing accelerator and…
Search for the neutrino mass and for cold dark matter in the Universe are at present two of the most exciting fields of particle physics and cosmology. This lecture will restrict itself on the search for neutralinos as cold dark matter, and…
From the observed results, we deduced that the mass of the neutrino is about 10^(-1) eV and the mass of the fourth stable elementary particle (delta) is about 10^(0) eV. While neutrino is related to electro-weak field, the fourth stable…
We examine the potential of using colliders to distinguish models with parity (Z_2) stabilized dark matter (DM) from models in which the DM is stabilized by other symmetries, taking the latter to be a Z_3 symmetry for illustration. The key…
We propose that dark matter consists of collections of atoms encapsulated inside pieces of an alternative vacuum, in which the Higgs field vacuum expectation value is appreciably smaller than in the usual vacuum. The alternative vacuum is…
Seesaw mechanism provides a natural explanation of light neutrino masses through suppression of heavy seesaw scale. In inverse seesaw models the seesaw scale can be much lower than that in the usual seesaw models. If terms inducing seesaw…
For the first time, we have a plausible and complete accounting of matter and energy in the Universe. Expressed a fraction of the critical density it goes like this: neutrinos, between 0.3% and 15%; stars, between 0.3% and 0.6%; baryons…
Neutron stars offer powerful astrophysical laboratories to probe the properties of dark matter. Gradual accumulation of heavy, non-annihilating dark matter in neutron stars can lead to the formation of comparable-mass black holes, and…
We investigate a scenario where the dark matter of the Universe is made from very light hidden photons transforming under a $Z_{2}$-symmetry. In contrast to the usual situation, kinetic mixing is forbidden by the symmetry and the dark…