Blazar

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Blazars (neologism from " BL Lacertae " and " Quasar " or abbreviation from " blazing quasi stellar objects "), sometimes also blasars , are a subclass of the active galactic nuclei that emit many times more radiation or particles than other galaxies . Further subclasses are radio galaxies , Seyfert galaxies and quasars. It is assumed that blazars differ from other active galactic nuclei by the direction of observation, which in blazars coincides with the direction of the relativistic jet ; in other words: a blazar is an active galactic nucleus whose particle jet “randomly” points towards earth.

Blazars are high-energy galactic objects from the center of which up to 50 percent of the radiation emitted by the entire galaxy comes. Currently the view is that the emitted energy escapes from the disc-shaped matter, which transforms a supermassive black hole in the core zone or activates it in the complex process of accretion and "devouring"; the energy radiation (jet beam) is perpendicular to the plane of the material flow. With the blazars, the emission of radiation energy or particles fluctuates much more strongly and faster (within hours to weeks) than with quasars. Blazars appear like a point source of light , strongly polarized and almost free of spectral lines . Such objects were first described by Benjamin Markarjan in the early 1960s .

Individual evidence

  1. ^ Matthew T. Whiting: Quasars and Blazars. Cape. 1 of the dissertation What made the quasar blush? Emission mechanisms in optically red quasars. University of Melbourne 2000.
  2. ↑ Claus Grupen: Astroparticle Physics: The universe in the light of cosmic rays. Springer 2001, ISBN 3540415424 . P. 166.
  3. ↑ Markus J. Aschwanden: Self-Organized Criticality in Astrophysics , Springer, Berlin-Heidelberg 2011, p. 246 ( available from Google Books )
  4. ^ Albrecht Unsöld, Bodo Baschek: The New Cosmos: An Introduction to Astronomy and Astrophysics. Springer 2001, ISBN 3540678778 . P. 441 ( available from Google Books).
  5. ↑ See e.g. B. Gaurang Yodh: Very high-energy gamma ray detectors , in: Beam Line 28/3 (1998), 12-23, here 20 ( available from Google Books).
  6. ↑ M. Bartelmann: An exciting neutrino? Physik Journal 17 (2018) No. 8/9 page 24

Web links

Wiktionary: Blazar  - explanations of meanings, word origins, synonyms, translations