Abstract
A method of using AGNs as cosmological probes and some recent results are discussed. The method is based on fitting the Hedgehog model to observations of spectra, structure and polarization of AGN radio emission and time variations of the observed quantities. If red shifts of selected AGNs are known, extragalactic distances, the Hubble constant and the deceleration parameter of the Universe can be measured using only radio observations. Recent results may give new strong arguments for the basic model to be in agreement with observations of variable spectra and structure of many AGNs, and may allow preliminary selection of AGNs for further use.
Similar content being viewed by others
References
Altschuler, D. R.: 1989,Fundament. Cosmic Phys. 14, 37
Kardashev, N. S.: 1969,Epilogue to Russian edition of: Burbidge, G.R. and Burbidge, E.M. Quasi Stellar Objects, Freeman (1967). Mir: Moscow
Kovalev, Yu. A. and Mikhailutsa, V. P.: 1980,Sov. Astron. 24, 400
Kovalev, Yu. A.: 1980,Sov. Astron. 24, 13
Kovalev, Yu. A.: 1984,Preprint No.879, Space Research Institute: Moscow
Kovalev, Yu. A.: 1994,Astron. Astrophys. Trans. 5, 67
Kovalev, Yu. A. and Kovalev, Y. Y.: 1993, in Davis, R. J. and Booth, R. S., ed(s).,Sub-arcsecond Radio Astronomy, Cambridge University Press: Cambridge, 371
Kovalev, Y. Y. and Larionov, G. M.: 1994,Sov. Astron. Lett. 20, 7
Kovalev, Y. Y.: 1995a,Sov. Astron. 72, (in press)
Kovalev, Y. Y.: 1995b,Astron. Astrophys. Trans., (in press)
Kurilchik, V. N.: 1972,Astrophys. Lett. 10, 115
Lang, K. R.: 1974,Astrophysical Formulae, Springer-Verlag: Berlin
Nesterov, N. S., Kovalev, Y. Y., Babak, S. V., and Larionov, G. M.: 1994,Sov. Astron. 71, 13
Nesterov, N. S., Kovalev, Y. Y., and Babak, S. V.: 1995, ?, (to be published)
Nizelski, N. A., Kovalev Yu. A. and Berlin A. B.: 1994, in Courvoisier T.J.-L. and Blecha A., ed(s).,Multi-wavelength Continuum Emission of AGN, Kluwer Academic Publishers: Dordrecht, p. 326
Ozernoj, L. M. and Ulanovskij, L. E.: 1974,Sov. Astron. 18, 4
Shklovskij I. S.: 1960,Astr. Zh. 37, 256
Van der Laan, H.: 1966,Nature 211, 1131
Woltjer, L.: 1966,Astrophys. J. 146, 597
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Kovalev, Y.A. Some active galactic nuclei as cosmological probes. Space Sci Rev 74, 475–479 (1995). https://doi.org/10.1007/BF00751436
Issue Date:
DOI: https://doi.org/10.1007/BF00751436