Related papers: Massive Tau Neutrino and SN 1987a
Supernova 1987A offers a unique opportunity to study an evolving supernova in unprecedented detail over several decades. The X-ray emission is dominated by interactions between the ejecta and the circumstellar medium, primarily the…
Core-collapse supernovae emit of order $10^{58}$ neutrinos and antineutrinos of all flavors over several seconds, with average energies of 10--25 MeV. In the Sudbury Neutrino Observatory (SNO), which begins operations this year, neutrinos…
A sensitivity study of the search for heavy sterile neutrinos ($\nu_H$) in the MeV mass range using solar neutrino experiments is presented. $\nu_H$, with masses ranging from a few MeV up to around 15 MeV, can be produced in the Sun through…
In this note, we analyze various constraints on the ``visible'' decay modes of a massive $\tau $ neutrino, $\nu_\tau\rightarrow\nu^\prime\,\gamma $ and $\nu_\tau\rightarrow\nu^\prime\, e^+ e^-$, where $\nu^\prime$ is a light neutrino. The…
Cherenkov telescopes could have the capability of detecting high energy tau neutrinos by searching for very inclined showers. If a tau lepton, produced by a tau neutrino, escapes from the Earth crust, it will decay and initiate an air…
High-energy muon- and electron-neutrinos yield a non-negligible flux of tau neutrinos as they propagate through Earth. In this letter, we address the impact of this additional component in the PeV and EeV energy regimes for the first time.…
The impact of unstable Majorana tau neutrinos on primordial nucleosynthesis is considered. The mass and lifetime of nu_tau are taken in the intervals 0.1-20 MeV and 0.001-400 sec respectively. The studied decay modes are nu_tau -> nu_mu +…
We discuss the effects of resonant $\nu_e \to \nu_s$ and $\bar{\nu}_e \to \bar{\nu}_s$ ($\nu_s$ is a sterile neutrino) conversions in the dense medium of a supernova. In particular, we assume the sterile neutrino $\nu_s$ to be in the hot…
Discovering neutrino decay would be strong evidence of physics beyond the Standard Model. Presently, there are only lax lower limits on the lifetime $\tau$ of neutrinos, of $\tau/m \sim 10^{-3}$ s eV$^{-1}$ or worse, where $m$ is the…
From a theoretical point of view, there is a strong motivation to consider an MeV-scale reheating temperature induced by long-lived massive particles with masses around the weak scale, decaying only through gravitational interaction. In…
We show that in the presence of sufficiently strong tau neutrino annihilations into majorons, the primordial nucleosynthesis constraints can not rule out tau neutrino masses in the MeV range.
We study three-flavor collective neutrino transformations in the dense-neutrino region above the neutrino sphere of a supernova core. We find that two-flavor conversions driven by the atmospheric mass difference and the 13-mixing angle…
We present a new overview of the life of very massive stars (VMS) in terms of neutrino emission from thermal processes: pair annihilation, plasmon decay, photoneutrino process, bremsstrahlung and recombination processes in burning stages of…
It has been recently proposed that a sterile neutrino \nu_h of mass m_h=40--80 MeV, mixing |U_{\mu h}|^2=10^{-3}--10^{-2}, lifetime \tau_h \lsim 10^{-9} s, and a dominant decay mode (\nu_h \to \nu_\mu \gamma) could be the origin of the…
Recently, the rapid multiwavelength photometry and flash spectra of supernova (SN) 2013fs imply that the progenitor stars of regular type II SNe (SNe II) might be commonly surrounded with a confined dense stellar wind ejected by themselves…
There has been a recent surge in interest in the detection of $\tau$ lepton-induced air showers from detectors at altitude. When a $\tau$ neutrino ($\nu_\tau$) enters the Earth it produces $\tau$ leptons as a result of nuclear charged…
The current picture of the collapse and explosion of massive stars and the formation of neutron stars is reviewed. According to the favored scenario, however by no means proven and undisputed, neutrinos deposit the energy of the explosion…
The best upper bounds on the masses of stable and unstable light neutrinos derive from the upper bound on the total mass density, as inferred from the lower limit $t_0> 13$ Gyr on the dynamical age of the Universe: If the Universe is…
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…
We study possible contributions of heavy sterile neutrinos $\nu_h$ to the decays $\tau^-\to e^{\pm}(\mu^{\pm})\pi^{\mp}\pi^-$. From the experimental upper bounds on their rates we derive new constraints on the $\nu_h-\nu_{\tau}$ mixing in…