相关论文: Neutrino Fluxes from Active Galaxies: a Model-Inde…
We present the theoretical arguments and describe the accumulating experimental evidence that jets, powered by supermassive black holes, are true cosmic accelerators. They produce photons of TeV energy, possible higher, and may be the…
Active galaxies and gamma ray bursts are the sources of the highest energy photons detected by astronomical telescopes. We speculate that they may be the sources of the highest energy cosmic rays. This makes them true proton accelerators,…
In this work, I present a qualitative discussion on the prospect of production of ultra-high photons in blazars. The sources are a subclass of active galactic nuclei which host supermassive black holes and fire relativistic jets into the…
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…
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.…
The observation of TeV-gamma rays of neutral pion origin from the supernova remnant RX J1713.7-3946 might have revealed the first specific site where protons are accelerated to energies typical of the main component of the cosmic rays. In…
A correlation between the highest energy Cosmic Rays (above ~ EeV) and the distribution of active galactic nuclei (AGN) gives rise to a prediction of neutrino production in the same sources. In this paper, we present a detailed AGN model,…
We review recently developed models of galactic discrete sources of high energy neutrinos. Some of them are based on a simple rescaling of the TeV $\gamma$-ray fluxes from recently detected galactic sources, such as, shell-type supernova…
Relativistic black-hole jet sources are leading candidates for high energy (>> TeV) neutrino production. The relations defining (a) efficient photopion losses of cosmic-ray protons on target photons and (b) gamma-gamma opacity of gamma rays…
Evidence for high-energy astrophysical PeV neutrinos has been found in the IceCube experiment from an analysis with a 7.5 year (2010 - 2017) data. Active galactic nuclei (AGN) are among the most prominent objects in the universe, and are…
Active galactic nuclei (AGN) with relativistic jets are the most powerful persistent astrophysical sources of electromagnetic radiation in the Universe. Blazars are the most extreme subclass of AGN with jets directed along the line of sight…
Top-down models of cosmic rays produce more neutrinos than photons and more photons than protons. In these models, we reevaluate the fluxes of neutrinos associated with the highest energy cosmic rays in light of mounting evidence that they…
Supermassive black holes in the centers of galaxies are very common. They are known to rotate, accrete, spin down and eject highly relativistic jets; those jets pointed at us all seem to show a spectrum with two strong bumps, one in the TeV…
Most active galactic nuclei (AGN) lack prominent jets, and show modest radio emission and significant X-ray emission which arises mainly from the galactic core, very near from the central black hole. We use a quantitative scenario of such…
We introduce neutrino astronomy 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 close to a century, we…
We discuss the possibility that microquasar jets may be powerful emitters of TeV neutrinos. We estimate the neutrino fluxes produced by photopion production in the jets of a sample of identified microquasars and microquasar candidates, for…
Powerful winds with wide opening angles, likely driven by accretion disks around black holes (BHs), are observed in the majority of active galactic nuclei (AGN) and can play a crucial role in AGN and galaxy evolution. If protons are…
The IceCube project transformed a cubic kilometer of transparent, natural Antarctic ice into a Cherenkov detector. It discovered neutrinos of TeV-PeV energy originating beyond our Galaxy with an energy flux that exceeds the one of…
The undisputed galactic origin of cosmic rays at energies below the so-called knee implies an existence of a nonthemal population of galactic objects which effectively accelerate protons and nuclei to TeV-PeV energies. The distinct…
Protons accelerated in the cores of active galactic nuclei can effectively produce neutrinos only if the soft radiation background in the core is sufficiently high. We find restrictions on the spectral properties and luminosity of blazars…