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Radio Active Nuclei

Published online by Cambridge University Press:  30 March 2016

K. I. Kellermann
K. I. Kellermann*
Affiliation:
National Radio Astronomy Observatory*

Extract

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For the purpose of this survey we shall use the term radio active nucleus to refer to compact radio sources which are found in galactic nuclei and which show activity either in the form of flux density variations or outward flow of material from the nucleus. There is great similarity between the observed properties of radio active nuclei with those of radio active quasars, and it is widely supposed that the quasar phenomena represents an extreme case of an active galaxy. In this paper however, we shall concentrate on compact radio sources found in the nuclei of identifiable galaxies, and quasars are discussed only to the extent that they help to understand the origin and evolution of radio active galactic nuclei.

Since radio active nuclei are typically in extent, they can be mapped only with VLBI techniques. Detailed maps are available for only a few of the strongest nuclei, but a much larger number can be identified from conventional interferometry with a resolution ~ 1”. In the few radio galaxies where most of the observed radio flux comes from the active nucleus, activity is observed directly on a time scale of months or even weeks. In others, it may be inferred from arguments based on synchrotron lifetime.

Type
Joint Discussions
Information
Highlights of Astronomy , Volume 6: Highlights of Astronomy. As presented at the XVIIIth General Assembly of the IAU, 1982 , 1983 , pp. 481 - 490
Copyright
Copyright © Reidel 1983

References

Angel, J.R.P., and Stockman, H.S.: 1980, Ann. Rev. 18, 321.Google Scholar
Arp, H.: 1981, ESO Workshop on Optical Jets in Galaxies.Google Scholar
Bartel, N. et al.: 1982, Astrophys. J. (in press)Google Scholar
Blandford, R.D., and Konigl, A.: 1979, Astrophys. J. 232, 34.CrossRefGoogle Scholar
Brown, R., and Lo, K-Y.: 1982, Astrophys. J. 253, 108.CrossRefGoogle Scholar
Condon, J.J., and Dressel, L.L.: 1978, Astrophys. J. 221, 456.CrossRefGoogle Scholar
Cohen, M.H., and Readhead, A.C.S.: 1979, Astrophys. J. Letters 233, L101.Google Scholar
Cohen, M.H., and Unwin, S.: 1981, IAU Symp. No. 97, Extragalactic Radio Sources, p. 345.Google Scholar
Crane, P.C.: 1979, Astron. J. 84., 281.CrossRefGoogle Scholar
Fiegelson, E.D.: 1981, IAU Symp. No. 97, Extragalactic Radio Sources, p. 107.Google Scholar
Fomalont, E.B.: 1980, IAU Symp. No. 94, The Origin of Cosmic Rays, p. 111.Google Scholar
Gopal-Krishna, et al.: 1980, Nature 288, 344.CrossRefGoogle Scholar
Heeschen, D.S., and Puschell, J.J.: 1982 (in press).Google Scholar
Jones, D.L. et al.: 1981, Astrophys. J. 247, L57.CrossRefGoogle Scholar
Kapahi, V.K., and Saikia, D.J.: 1981, Bulletin of the Astronomical Society of India 9, 177.Google Scholar
Kapahi, V.K., and Saikia, D.J.: 1982, Indian Journal of Astrophysics and Astronomy (in press).Google Scholar
Kaufmann, et al.: 1981, Astron. & Astrophys. 100, 189.Google Scholar
Kellermann, K.I. et al.: 1975, Astrophys. J. Letters 197, L113.CrossRefGoogle Scholar
Kellermann, K.I. et al.: 1976, Astrophys. J. Letters 210, L121.CrossRefGoogle Scholar
Kellermann, K.I. et al.: 1978, Physica Scripta 17, 257.CrossRefGoogle Scholar
Kellermann, K.I. et al. : 1981, Astron. & Astrophys. 97, LI.Google Scholar
Linfield, R.: 1981a, Astrophys. J. 244, 436.CrossRefGoogle Scholar
Linfield, R.: 1981b, Astrophys. J. 250, 464.CrossRefGoogle Scholar
Lo, K.Y. et al. : 1981, Astrophys. J. 249, 504.CrossRefGoogle Scholar
Owen, F.N. et al.: 1980, Astrophys. J. Letters 239, L11.CrossRefGoogle Scholar
Preuss, E. et al.: 1977, Astron. & Astrophys. 54, 297.Google Scholar
Preuss, E. et al.: 1980, Astrophys. J. Letters 240, L7.CrossRefGoogle Scholar
Preuss, E.: 1981, ES0/EAS Workshop on Jets, p. 97.Google Scholar
Preuss, E. et al.: 1981, IAU Symp. No. 97, Extragalactic Radio Sources, p. 289.Google Scholar
Reid, M. et al.: 1982, Astrophys. J. (in press).Google Scholar
Romney, J. et al.: 1981, IAU Symp. No. 97, Extragalactic Radio Sources, p. 291.Google Scholar
Saikia, D.J.: 1981a, Monthly Notices Roy. Astron. Soc. 197, 1097.CrossRefGoogle Scholar
Saikia, D.J.: 1981b, Monthly Notices Roy. Astron. Soc. 197, 11p.CrossRefGoogle Scholar
Saikia, D.J., and Wiita, P.J.: 1982, Monthly Notices Roy. Astron. Soc. 200, 83.CrossRefGoogle Scholar
Scheuer, P. and Readhead, A.C.S.: 1979, Nature 277, 182.CrossRefGoogle Scholar
Schilizzi, R.T.: 1976, Astron. J. 81, 946.CrossRefGoogle Scholar
Schilizzi, R.T. et al.: 1979, Astronomy & Astrophys. 77, 1.Google Scholar
Shaffer, D.B. et al.: 1981, IAU Symp. No. 97, Extragalactic Radio Sources, p. 367.Google Scholar
Shaffer, D.B., and Marscher, A.P.: 1979, Astrophys. J. Letters 233, L105.CrossRefGoogle Scholar
Simkin, S.: 1977, Astrophys. J. 217, 145.CrossRefGoogle Scholar
Strittmatter, P.A. et al.: 1980, Astron. & Astrophys. 88, L12.Google Scholar
Unwin, S. et al.: 1982, Astrophys. J. 256, 83.CrossRefGoogle Scholar
von, Groningen et al.: 1980, Astronomy & Astrophys. 90, L7.Google Scholar
Walker, R.C. et al.: 1982, Astrophys. J. 257, 56.CrossRefGoogle Scholar
Young, P. et al.: 1978, Astrophys. J. 221, 721.CrossRefGoogle Scholar