Related papers: Diffuse flux of PeV neutrinos from centrifugally a…
A several-step theoretical model is constructed to trace the origin of ultra high energy (UHE) $[1-2]$PeV neutrinos detected, recently, by the IceCube collaboration. Protons in the AGN magnetosphere, experiencing different gravitational…
Mysteries about the origin of high-energy cosmic neutrinos have deepened by the recent IceCube measurement of a large diffuse flux in the 10-100 TeV range. Based on the standard disk-corona picture of active galactic nuclei (AGN), we…
The origins of the diffuse flux of cosmogenic PeV neutrinos detected in the IceCube experiment during 2010 - 2017 remain unidentified. A population of extragalactic newly born fast spinning pulsars are investigated as possible candidates…
Recently IceCube collaboration has reported first evidence for the astrophysical neutrinos. Observation corresponds to the total astrophysical neutrino flux of the order of $3 \cdot 10^{-8}$ $GeV/cm^2/s/sr$ in a PeV energy range. Active…
The IceCube Neutrino Observatory has detected high-energy astrophysical neutrinos in the TeV-PeV range. These neutrinos have an isotropic distribution on the sky, and therefore, likely originate from extragalactic sources. Active Galactic…
IceCube observations point to Active Galactic Nuclei (AGN) as promising contributors to the observed astrophysical neutrino flux. Close to the central black hole, protons can be accelerated through magnetic reconnection to very high…
We investigate the possibility that radio-bright active galactic nuclei (AGN) are responsible for the TeV--PeV neutrinos detected by IceCube. We use an unbinned maximum-likelihood-ratio method, 10 years of IceCube muon-track data, and 3388…
Active galactic nuclei (AGN) can accelerate protons to energies of $\sim$10-100 TeV, with secondary production of high-energy neutrinos. If the acceleration is driven by magnetized turbulence, the main properties of the resulting proton and…
Active Galactic Nuclei (AGN) are believed to be one of the main source candidates for the high-energy (TeV-PeV) cosmic neutrino flux recently discovered by the IceCube neutrino observatory. Nevertheless, several correlation studies between…
The IceCube experiment recently detected the first flux of high-energy neutrinos in excess of atmospheric backgrounds. We examine whether these neutrinos originate from within the same extragalactic sources as ultrahigh-energy cosmic rays.…
IceCube is a cubic-kilometer Cherenkov telescope operating at the South Pole. In 2013 IceCube discovered high-energy astrophysical neutrinos and has more recently found compelling evidence for a flaring blazar being a source of high-energy…
The detection of astrophysical very high energy (VHE) neutrinos in the range of TeV-PeV energies by the IceCube observatory has opened a new season in high energy astrophysics. Energies ~PeV imply that the neutrinos are originated from…
Active Galactic Nuclei (AGN) are powerful astronomical objects with very high luminosities. Theoretical arguments suggest that these objects are capable of accelerating particles to energies of 10$^{20}$ eV. In environments with matter or…
The enigmatic origin of the diffuse neutrino background detected by IceCube in the energy range from TeV to PeV remains one of the central open problems in high-energy astrophysics, and this puzzle is further deepened by the recent evidence…
The IceCube collaboration has recently reported the observation of two events with energies in excess of 1 PeV. While an atmospheric origin of these events cannot be ruled out at this time, this pair of showers may potentially represent the…
The observed very high energy spectra of distant blazars are well described by secondary gamma rays produced in line-of-sight interactions of cosmic rays with background photons. In the absence of the cosmic-ray contribution, one would not…
IceCube has measured a diffuse astrophysical flux of TeV-PeV neutrinos. The most plausible sources are unique high energy cosmic ray accelerators like hypernova remnants (HNRs) and remnants from gamma ray bursts in star-burst galaxies,…
We discuss the possibility that the PeV neutrinos recently observed by IceCube are produced by the interactions of extragalactic cosmic rays during their propagation through the radiation backgrounds. We show that the fluxes resulting from…
With the breakthrough in PeV gamma-ray astronomy brought by the LHAASO experiment, the high-energy sky is getting richer than before. Lately, LHAASO Collaboration reported the observation of a gamma-ray diffuse emission with energy up to…
Active galactic nuclei (AGN) are known as sources of high energy gamma-rays. The emission probably results from non-thermal radiation of relativistic jets belonging to the AGN. Earlier investigations of these processes have suggested that…