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Physical processes in active galactic nuclei

  • Roland Svensson
7. Active Galactic Nuclei
Part of the Lecture Notes in Physics book series (LNP, volume 255)

Abstract

Active galactic nuclei (AGNs) emit continuum radiation evenly spread over up to ten decades in frequency from the radio into the gamma-ray range. Plausible emission mechanisms and their characteristics are reviewed. In the deep potential wells around black holes the mean energy per proton can reach 100 MeV. Part or all of this energy may be channeled to all electrons equally (thermal plasma) or, preferentially, into only a small fraction of the electrons (nonthermal plasma). In the former case thermal Comptonization of soft photons may be the dominant emission mechanism, while in the latter case the synchrotron and the inverse Compton scattering process (synchro-self-Compton) are likely to dominate.

Keywords

Black Hole Pair Production Optical Depth Spectral Index Active Galactic Nucleus 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1976

Authors and Affiliations

  • Roland Svensson
    • 1
  1. 1.NORDITACopenhagen ØDenmark

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