Abstract
DISTANT radio galaxies provide valuable insights into the properties of the young Universe—they are the only known extended optical sources at high redshift and might represent an early stage in the formation and evolution of galaxies in general. This extended optical emission often has very complex morphologies, but the origin of the light is still unclear. Here we report spectroscopic observations for several distant radio galaxies (0.75≤ z ≤ 1.1) in which the rest-frame spectra exhibit featureless continua between 2,500 Å and 5,000 Å. We see no evidence for the break in the spectrum at 4,000 Å expected for an old stellar population1–3, and suggest that young stars or scattered emissions from the active nuclei are responsible for most of the observed light. In either case, this implies that the source of the optical emission is com-parable in age to the associated radio source, namely 107 years or less.
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
Lilly, S. J. Astrophys. J. 340, 77–89 (1989).
Rigler, M. A., Lilly, S., Stockton, A., Hammer, F. & Le Fevre, O. Astrophys. J. 385, 61–82 (1992).
Chambers, K. C. & Chariot, S. Astrophys. J. 348, L1–L4 (1990).
Spinrad, H. Publs. astr. Soc. Pacific 98, 269–284 (1986).
Rawlings, S., Eales, S. A. & Lacy, M. Mon. Not R. astr. Soc. 251, 17P–21P (1991).
Hammer, F. & Le Fevre, O., Astrophys. J. 357, 38–49 (1990).
Hammer, F., Le Fevre, O. & Proust, D. Astrophys. J. 374, 91–104 (1991).
Spinrad, H., Djorgovski, S., Marr, J. & Aguilar, L. Publs. astr. Soc. Pacific 97, 932–961 (1985).
Bithell, M. & Rees, M. J. Mon. Not. R. astr. Soc. 242, 570–575 (1990).
Le Fèvre, O. & Hammer, F. astr. Astrophys. 254, L29–L32 (1992).
Bruzual, A. G. Astrophys. J. 273, 105–127 (1983).
Bica, E. Astr. Astrophys. 195, 76–92 (1988).
Chambers, K. C. & McCarthy, P. J. Astrophys. J. 354, L9–L12 (1990).
Yates, M. G., Miller, L. & Peacock, J. A. Mon. Not. R. astr. Soc. 221, 311–317 (1986).
Rees, M. J. Mon. Not. R. astr. Soc. 428, 1P–4P (1989).
van Breugel, W. & McCarthy, P. J. in Proc. ESO Workshop on Extranuclear Activity in Galaxies (eds Fosbury, R. & Meurs, E.) (ESO, Garching, 1989).
di Seregho Alighieri, S., Fosbury, R., Quinn, P. & Tadhunter, C. Nature 341, 307–309 (1989).
Tadhunter, C. N., Scarrott, S. M., Draper, P. & Rolph, C. Mon. Not. R. astr. Soc. 256, 53P–58P (1992).
Januzzi, B. T. & Elston, R. Astrophys. J. 351, L9–L12 (1991).
Heckman, T. M., Chambers, K. C. & Postman, M. Astrophys. J. 391, 39–47 (1992).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Hammer, F., Fèvre, O. & Angonin, M. A young source of optical emission from distant radio galaxies. Nature 362, 324–326 (1993). https://doi.org/10.1038/362324a0
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/362324a0
This article is cited by
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.