Abstract
In a previous paper1 we reported the discovery of an extended steep-spectrum radio lobe located ∼34 arc min north-east of the galactic centre (the northern galactic centre lobe). Based on the similarity of the observed properties of this object to the radio lobes observed in the nuclei of Seyfert galaxies2, we suggested that this source may be a manifestation of nuclear activity associated with the compact non-thermal source3 located at the galactic centre. However, no clear evidence for a second opposing lobe was evident from the 80-MHz observations. Here we report observations at 110.6 and 123.0MHz which confirm the existence of a second steep-spectrum feature, first discovered by Yusef-Zadeh et al.4 at 160 MHz, which extends ∼10 arc min to the south-east of the radio source Sagittarius-A. These new observations are in the only frequency range in which it is possible to view both of these features simultaneously and to display their morphology as a function of frequency. At lower frequencies the features are obscured by thermal absorption; at higher frequencies they blend into the background emission. Based on this unique perspective, we propose that these radio sources are related, and associated with activity at the galactic nucleus.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
LaRosa, T. N. & Kassim, N. E. Astrophys. J. 299, L13–L17 (1985).
Ulvestad, J. S. & Wilson, A. S. Astrophys. J. 285, 439–452 (1984).
Lo, K. Y. et al. Nature 315, 124–126 (1985).
Yusef-Zadeh, F., Morris, M., Slee, O. B. & Nelson, G. J. Astrophys. J. 300, L47–L50 (1986).
Erickson, W. C., Mahoney, M. J. & Erb, K. Astrophys. J. Suppl. Ser. 50, 403–419 (1983).
Baars, J. W. M., Genzel, R., Pauliny-Toth, I. I. K. & Witzel, A. Astr. Astrophys. 61, 99–106 (1977).
Brezgunov, V. N., Dagkesamansky, R. D. & Udal'tsov, V. A. Astrophys. Lett. 9, 117–119 (1971).
Dulk, G. A. & Slee, O. B. Nature 248, 33–34 (1974).
Dent, W. A. et al. in The Galactic Center (eds Reigler, G. R. & Blandford, R. D.) 33–41 (American Institute of Physics, New York, 1982).
Tsuboi, M., Inoue, M., Handa, T., Tabara, H. & Kato, T. Publs astr. Soc. Japan 37, 359–368 (1985).
Seiradakis, J. H., Lasenby, A. N., Yusef-Zadeh, F., Wielebinski, R. & Klein, U. Nature 317, 697–699 (1985).
Wilson, A. S. in Extragalactic Radio Astronomy (eds Heeschen, D. S. & Wade, C. M.) 179–188 (Reidel, Dordrecht, 1981).
Duric, N., Seaquist, E. R., Crane, P. C., Bignell, R. C. & Davis, L. E. Astrophys. J. 273, L11–L15 (1983).
Hummel, E., van Gorkom, J. H. & Kotanyi, C. G. Astrophys. J. 267, L5–L9 (1983).
Jones, D. L., Sramek, R. A. & Terzian, Y. Astrophys. J. 246, 28–37 (1981).
Keel, W. C. Astrophys. J. 269, 466–486 (1983).
Stocke, J. T., Bums, J. O. & Christiansen, W. A. Astrophys. J. 299, 799–813 (1985).
Begelman, M. C., Blandford, R. D. & Rees, M. J. Rev. mod. Phys. 56, 225–351 (1984).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Kassim, N., LaRosa, T. & Erickson, W. Steep-spectrum radio lobes near the galactic centre. Nature 322, 522–524 (1986). https://doi.org/10.1038/322522a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/322522a0
This article is cited by
-
Particle energization in galactic centre ejections
Astrophysics and Space Science (1991)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.
