Related papers: Phase--space Distribution of Volatile Dark Matter
Four zero neutrino Yukawa textures in a specified weak basis, combined with $\mu\tau$ symmetry and type-I seesaw, yield a highly constrained and predictive scheme. Two alternately viable $3\times3$ light neutrino Majorana mass matrices…
Cosmological limits on neutrino masses are softened, by more than a factor 2, if Cold Dark Matter (CDM) and Dark Energy (DE) are coupled. In turn, a neutrino mass yielding $\Omega_\nu$ up to $\sim0.20$ allows coupling levels $\beta \simeq…
An extension of the Standard Model by three right-handed neutrinos with masses smaller than the electroweak scale (the $\nu$MSM) can explain simultaneously dark matter and baryon asymmetry of the Universe, being consistent with the data on…
Neutrino physics is used as an illustrative example for an elementary introduction to the computational method of Feynman loop-diagrams and decay rates. If the neutrinos are as massive as recently reported by the Super-Kamiokande results,…
Due to sphaleron processes in the high-temperature symmetric phase of the standard model the cosmological baryon asymmetry is related to neutrino properties. For hierarchical neutrino masses, with $B-L$ broken at the unification scale…
We consider massive Dirac electron antineutrino to be observed in the muon decay, $\mu^{-} \rightarrow e^- +\bar{\nu}_{e} + \nu_{\mu}$, at rest in the LAB reference frame. A computation of $\bar{\nu}_{e}$ differential direct spectral shape…
The physics goals of NOvA are the constraints of neutrino oscillation parameters such as the octant of $\theta_{23}$, $\delta_{\rm{CP}}$, and the neutrino mass hierarchy via a joint fit to $\nu_{\mu}$ and $\nu_{e}$ oscillation spectrum. We…
Right-handed neutrinos ($\nu_{R}$) offer an intriguing portal to new physics in hidden sectors where dark matter (DM) may reside. In this work, we delve into the simplest hidden sector involving only a real scalar exclusively coupled to…
We demonstrate that a scalar field is unable to reverse its direction of motion while continuously exchanging energy with another fluid. If the rate of transfer is modulated by the scalar's acceleration, the field can undergo a rapid…
We discuss the propagation of dark matter perturbations with non-zero velocity dispersion in cosmological models. In particular a non-zero massive neutrino component may well have a significant effect on the matter power spectrum and cosmic…
We present a description of cosmic neutrinos as a dispersive fluid. In this approach, the neutrino phase space is reduced to density and velocity fields alongside a scale-dependent sound speed. This sound speed depends on redshift, the…
We study a mechanism to make dark matter stable based on the Pauli blocking in the fermion background. In the background where fermions occupy the states, the decay of dark matter to those final states is not allowed, as a result, DM…
Despite direct observations favoring a low mass density, a critical density universe with a neutrino component of dark matter provides the best existing model to explain the observed structure of the universe over more than three orders of…
In this paper we consider the coherence properties of neutrinos produced by the decays of pions in conventional neutrino beams. Using a multi-particle density matrix formalism we derive the oscillation probability for neutrinos emitted by a…
We discuss possibility of describing solar, atmospheric and LSND results with four neutrinos forming two quasi-degenerate pairs. The simplest versions of this 2+2 scheme with either $\nu_e$ or $\nu_\mu$ mixing exclusively with sterile…
The absolute stability of a dark matter (DM) particle is not a binding requirement. Here we suggest a few scenarios where the DM particle is liable to decay via extremely feeble interactions. This can happen via inexplicably small Yukawa…
Effects of the dense matter can induce the neutrino decay even if neutrinos are stable in vacuum. This is due to coherent interactions with matter which lead to energy level-splitting between the neutrino and antineutrino states and thereby…
Using a real-time formalism of equilibrium and nonequilibrium quantum-field theory, we derive the reaction-rate formula for neutrino-conversion ($\nu \to \nu'$) process and $\nu \bar{\nu}'$ annihilation process, which take place in a hot…
A muon collider is expected to produce a high intensity neutrino beam which is an admixture of either $\nu_{\mu}+\bar{\nu_e}$ or $\bar{\nu}_{\mu} +\nu_e$ which can can be directed to underground detectors far away from the source. It will…
The observed flavor oscillations of solar and atmospheric neutrinos determine several elements of the leptonic mixing matrix, but leave open the small mixing angle Theta_13, a possible CP-violating phase, the mass ordering, the absolute…