Astrophysics and Space Science

, Volume 82, Issue 1, pp 199–207 | Cite as

Seyfert galaxies and the cosmic γ-ray diffuse background

  • L. Bassani
  • R. C. Butler
  • A. J. Dean
  • G. Di Cocco
  • F. Perotti
  • G. Villa


Three active galaxies, generally classified as Seyferts, have been discovered recently to be powerful, low energy γ-ray sources. The similarity between their spectral characteristics and those of the cosmic background at γ-ray energies suggests that these objects could make a significant contribution to this diffuse flux. This contribution has been assessed using two different number densities of γ-ray-emitting Seyfert galaxies based on optical and X-ray data. The comparison of the estimated and measured diffuse γ-ray background intensities is used to gain a deeper understanding of the metabolism of Seyfert galaxies.


Spectral Characteristic Significant Contribution Deep Understanding Diffuse Flux Background Intensity 
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

© D. Reidel Publishing Co 1982

Authors and Affiliations

  • L. Bassani
    • 1
  • R. C. Butler
    • 1
  • A. J. Dean
    • 1
  • G. Di Cocco
    • 2
  • F. Perotti
    • 3
  • G. Villa
    • 3
  1. 1.Physics DepartmentUniversity of SouthamptonSouthamptonU.K.
  2. 2.Istituto TESREBolognaItaly
  3. 3.Istituto Fisica CosmicaMilanoItaly

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