Related papers: Why Neutrino Lines are Hypersharp
It has been suggested that ultrahigh energy neutrinos can acquire cross-sections approaching hadronic size if the string scale is as low as 1-10 TeV. In this case, the vertical air showers observed with energies above the…
The neutron, besides its $\beta$-decay $n\to p e\bar\nu_e$, might have a new decay channel $n\to n' X$ into mirror neutron $n'$, its nearly mass degenerate twin from parallel dark sector, and a massless boson $X$ which can be ordinary and…
``Top--down'' models explain the observation of ultra high energy cosmic rays (UHECR; $E \gsim 5 \cdot 10^{19}$ eV) through the decay of very massive, long--lived ``$X$ particles''. If superparticles with masses near a TeV exist, $X$ decays…
Terrestrial and ``Heavenly'' experiments severely constrain the mass and lifetime of an MeV tau neutrino. Irrespective of decay mode, for $\tau_\nu \ga 300\sec$ the mass of the tau neutrino must be either approximately $30\MeV$ or less than…
The sum of the masses of the three neutrino mass eigenstates is now constrained both from above and below, and lies between 55 and 6900 meV. The lower limit is set by neutrino oscillations and the fact that masses are non-negative. The…
We analyze the influence of decaying sterile neutrinos with the masses in the range 1-140 MeV on the primordial Helium-4 abundance, explicitly solving the Boltzmann equations for all particle species, taking into account neutrino flavour…
The radiative decay $\nu_H \to \nu_L + \gamma$ of massive neutrinos is analyzed in the framework of the standard model with lepton mixing for very strong magnetic fields $B\gg B_{cr} = m_e^2/e \sim 4.14 \times 10^{13}$G. The analysis is…
The origin of the highest-energy cosmic rays remains elusive. The decay of a superheavy particle (X) into an ultra-energetic neutrino which scatters from a relic (anti-)neutrino at the Z-resonance has attractive features. Given the…
It has been suggested that a potentially large fraction of supernovae could be accompanied by relativistic outflows that stall below the stellar surface. In this letter we point out that internal shocks that are believed to accelerate…
We study the growth of density perturbations in a universe with unstable dark matter particles. The mass (m_\nu) range 30 eV < m_\nu < 10 keV with lifetimes ($t_d$) in the range 10^7 sec < t_d < 10^16 sec are considered. We calculate the…
Cross sections for the interactions of ultrahigh-energy neutrinos with nucleons are evaluated in light of new information about nucleon structure functions. For $10^{20}$--eV neutrinos, the cross section is about 2.4 times previous…
Decaying topological defects, in particular cosmic strings, can produce a significant flux of high energy neutrinos, photons and cosmic rays. According to the prevailing understanding of cosmic string dynamics in an expanding Universe, the…
For the first time the antineutrino spectrum formed as a result of neutron and tritium decays during the epoch of primordial nucleosynthesis is calculated. This spectrum is a non-thermal increase in addition to the standard cosmic neutrino…
We explain the existence of neutrino masses and their flavor structure, dark matter relic abundance and the observed 3.5 keV X-ray line within the framework of a gauged $U(1)_{L_{\mu} - L_{\tau}}$ extension of the "scotogenic" model. In the…
If neutrinos have mass, they can also decay. Decay lifetimes of cosmological interest can be probed, in principle, through the detection of the redshifted, diffuse neutrino flux produced by all past supernovae--the so-called supernova relic…
Dark Matter particles in the Galactic Center and halo can annihilate or decay into a pair of neutrinos producing a monochromatic flux of neutrinos. The spectral feature of this signal is unique and it is not expected from any astrophysical…
We consider the possibility of solar neutrino decay as a sub-leading effect on their propagation between production and detection. Using current oscillation data, we set a new lower bound to the $\nu_2$ neutrino lifetime at $\tau_2\, /\,…
The $220^{+570}_{-100}\,$PeV neutrino detected by KM3NeT marks the beginning of ultra-high-energy neutrino astronomy and provides a powerful probe of Lorentz Invariance Violation (LIV). In superluminal scenarios, neutrinos can decay through…
Superheavy particles of masses $\simeq 10^{13}-10^{14} GeV$ with lifetimes $\simeq 10^{10}-10^{22} years$ are very interesting, since their decays may account for the ultra-high energy (UHE) cosmic rays discovered beyond the…
Environmental decoherence of oscillating neutrinos of strength $\Gamma = (2.3 \pm 1.1) \times 10^{-23}$ GeV can explain how maximal $\theta_{23}$ mixing observed at 295 km by T2K appears to be non-maximal at longer baselines. As shown…