Cosmic Rays, Gamma Rays and Neutrinos from Point Sources

Abstract

The suggestion has been made that the energy spectrum from point sources such as AGN (Active Galactic Nuclei) and GBHC (Galactic Black Hole Candidates) is universal, irrespective of the nature of the emitted particles. A comparison of the energy spectrum for cosmic rays at the source and $γ$-rays from quasars obtained recently by CGRO (Compton Gamma Ray Observatory) indicates that the prediction is in agreement with the data in the average sense. This suggests that neutrinos from point sources should have a spectral index identical to that of $γ$-rays for an individual point source. This prediction is also consistent with the recent observation of neutrinos by Kamiokande and IMB in which the ratio of $ν_μ/ν_e$ is close to 1, instead of 2 as expected from atmospheric neutrinos. For a further test of the model, analysis of the time variation of $γ$-ray spectra from quasars is suggested.