Cosmic rays from active galactic nuclei and in metagalactic space

Abstract

view Abstract Citations (15) References (23) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Cosmic rays from active galactic nuclei and in metagalactic space Shapiro, M. M. ; Silberberg, R. Abstract The mean energy density of cosmic rays in the supercluster is determined. Developments in extragalactic cosmic rays since the study of Ginzburg and Syrovatskii (1972) are summarized, and order-of-magnitude estimates of extragalactic protons are made from observations of extensive air showers initiated by cosmic rays at energies above 10 to the 19th eV. Three arguments that these ultrahigh energy air showers are generated by extragalactic protons and other nuclei are stated. It is assumed that cosmic rays about 10 to the 19th eV are of extragalactic origin, and whether this energy density is consistent with the nonthermal energy output from extragalactic sources within the supercluster, and whether normal galaxies therein could provide this energy density, is investigated. A lower limit to the age of extragalactic cosmic rays of 50 million years is deduced, with an upper limit of slightly above 100 million years for the highest energy rays. Publication: The Astrophysical Journal Pub Date: February 1983 DOI: 10.1086/160700 Bibcode: 1983ApJ...265..570S Keywords: Active Galactic Nuclei; Cosmic Rays; Galactic Radiation; Flux Density; Galactic Clusters; Milky Way Galaxy; Protons; Space Radiation full text sources ADS |