Related papers: Neutrino Conversions in Active Galactic Nuclei
We show that all features of the ultrahigh energy cosmic ray spectrum from 10^{17} eV to 10^{21} eV can be described with a simple power-like injection spectrum of protons under the assumption that the neutrino-nucleon cross-section is…
This is a review of high energy neutrino astronomy that might be done with a kilometer-scale detector. The emphasis is on diffuse neutrinos of extragalactic origin and their relation to possible sources of the highest energy cosmic rays,…
Some generalizations of the relation between high-energy astrophysical neutrino and cosmic ray fluxes are obtained, taking into account present results on the cosmic ray spectrum and composition as well as a more realistic modeling of the…
The hypothesis that high energy cosmic neutrinos are power law distributed is critically analyzed. We propose a model with two components that explains better the observations. The extragalactic component of the high energy neutrino flux…
Supernovae (SN) and supernova remnants (SNR) have key roles in galaxies, but their physical descriptions is still incomplete. Thus, it is of interest to study neutrino radiation to understand SN and SNR better. We will discuss: (1) The ~10…
Ultra-high-energy cosmic rays (UHECR) scattering off the cosmic relic neutrino background have recently gained renewed interest in the literature. Current data suggest that (UHECR) are predominantly made of heavy nuclei. Similar to the…
This review describes telescopes designed to study neutrinos from astrophysical sources. These sources include the Sun and Supernovae emitting neutrino energies up to tens of MeV, atmospheric neutrino sources caused by cosmic ray…
High-energy neutrinos are detected by the IceCube Observatory in the direction of NGC 1068, the archetypical type II Seyfert galaxy. The neutrino flux, surprisingly, is more than an order of magnitude higher than the $\gamma$-ray upper…
The main goal of the construction of large volume, high energy neutrino telescopes is the detection of extra-Galactic neutrino sources. The existence of such sources is implied by observations of ultra-high energy, >10^{19} eV, cosmic-rays…
The rare detections of astrophysical neutrinos with energies above 5~PeV by two neutrino telescopes underscore the existence of a flux at these energies. In addition to over a decade of data taken by the IceCube Neutrino Observatory, the…
It is assumed that neutrino-nucleon scattering at ultra-high energies effectively proceeds through excitations of leptoquarks in neutrino-quark subprocesses. This approach reproduces the behavior of the energy dependence of the ultra-high…
The recent IceCube detection of TeV neutrino emission from the nearby active galaxy NGC 1068 suggests that active galactic nuclei (AGN) could make a sizable contribution to the diffuse flux of astrophysical neutrinos. The absence of TeV…
We study ultrahigh energy astrophysical neutrinos and their interactions within the Standard Model and beyond. We consider propagation of muon neutrinos, tau neutrinos that originate in $\nu_\mu \to \nu_\tau$ oscillations, and tau leptons…
The observation of high-energy extraterrestrial neutrinos is one of the most promising future options to increase our knowledge on non-thermal processes in the universe. Neutrinos are e.g. unavoidably produced in environments where…
We introduce neutrino astronomy starting from the observational fact that Nature accelerates protons and photons to energies in excess of 10^{20} and 10^{13} eV, respectively. Although the discovery of cosmic rays dates back a century, we…
Neutrino interactions with nuclei have been the subject of intense interest over the last 15 years. Current and future measurements of neutrino oscillation and exotic physics use order 0.1--10 GeV neutrinos on a range of nuclear targets…
High energy neutrino astrophysics has come of age with the discovery by IceCube of neutrinos in the TeV to PeV energy range attributable to extragalactic sources at cosmological distances. At such energies, astrophysical neutrinos must have…
The merger of a neutron star (NS) binary may result in the formation of a long-lived, or indefinitely stable, millisecond magnetar remnant surrounded by a low-mass ejecta shell. A portion of the magnetar's prodigious rotational energy is…
We consider the possibility that the excess of cosmic rays near $\sim 10^{18}$ eV, reported by the AGASA and SUGAR groups from the direction of the Galactic Center, is caused by a young, very fast pulsar in the high density medium. The…
Annihilation of high energy, $\sim 10^{21}$eV, neutrinos on big bang relic neutrinos of $\sim 1$eV mass, clustered in the Galactic halo or in a nearby galaxy cluster halo, has been suggested to generate, through hadronic Z decay, high…