Astrophysics and Space Science

, Volume 79, Issue 2, pp 469–481 | Cite as

The γ-ray emission from the Seyfert galaxy NGC 4151

  • L. Bassani


Light curves at X-ray, ultraviolet, optical and infrared wavelengths of NGC 4151 over the period 1977–1980 are presented together with a summary of the large amount of observational data relating to this Seyfert galaxy. Intensity variations in different wavebands are discussed and compared with recent low energy γ-ray observations of this object. The positive measurement of gamma-radiation in May 1977 is shown to have been characterised by a high optical state and a possible infrared maximum. The data presented are compared with the predictions of some emission mechanisms, which have been proposed to account for the gamma-radiation. In particular, a synchrotron self-Compton model, which relates the infrared/optical emission to the X-ray/low energy γ-ray emission is discussed.


Observational Data Intensity Variation Light Curve Positive Measurement Optical State 
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 1981

Authors and Affiliations

  • L. Bassani
    • 1
  1. 1.Department of PhysicsSouthampton UniversitySouthamptonEngland

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