Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-28T05:34:34.906Z Has data issue: false hasContentIssue false

High Redshift Radio Galaxies

Published online by Cambridge University Press:  25 May 2016

James S. Dunlop*
Affiliation:
Astrophysics, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The potentially important role of jet-cloud interactions in determining the appearance of high-redshift radio galaxies is discussed and investigated via new 3-dimensional simulations of off-axis jet-cloud collisions. The results indicate that the most powerful radio sources are likely to be observed during or shortly after a jet-cloud interaction, and that such interactions can explain both the radio structures and the spatial association between optical and radio light found in powerful radio galaxies at high redshift. It is argued that, due to the radio-power dependence of such complicating effects, the optical-infrared colours and morphologies of very radio-luminous high-redshift galaxies can tell us essentially nothing about their evolutionary state. Either one must study much less radio-luminous sources in which the AGN-induced contamination is minimised, or one must attempt to determine what fraction of the baryonic mass of the radio galaxy has been converted into stars at the epoch of observation. Recent observations aimed at performing the latter experiment on two well-known high-redshift radio galaxies (4C 41.17 & B2 0902+34) are described. It is concluded that at present there exists no clear evidence that either of these famous galaxies is ‘primæval’; on the contrary, the continued low-dispersion of the infrared Hubble diagram at z > 2 points toward a much higher redshift of formation for elliptical galaxies.

Type
Part I: Invited Reviews
Copyright
Copyright © Kluwer 1996 

References

Barthel, P.D. & Miley, G.K., 1987. Nature, 333, 319.CrossRefGoogle Scholar
Carilli, C.L., Owen, F. & Harris, D.E., 1993. AJ, 107, 480.CrossRefGoogle Scholar
Chambers, K.C., Miley, G.K. & van Breugel, W.J.M., 1987. Nature, 329, 624.CrossRefGoogle Scholar
Chambers, K.C., Miley, G.K. & van Breugel, W.J.M., 1990. ApJ, 363, 21.CrossRefGoogle Scholar
Daly, R.A., 1992. ApJ, 386, L9.CrossRefGoogle Scholar
De Young, D.S., 1991. ApJ, 371, 69.CrossRefGoogle Scholar
Dickinson, M., 1995. In: ‘Galaxies in the Young Universe’, Ringberg Workshop Sep 1994, in press.Google Scholar
Dunlop, J.S. & Peacock, J.A., 1993. MNRAS, 263, 936.CrossRefGoogle Scholar
Dunlop, J.S. & Peacock, J.A., 1995. In: ‘Galaxies in the Young Universe’, Ringberg Workshop Sep 1994, in press.Google Scholar
Dunlop, J.S. et al., 1994. Nature, 370, 347.CrossRefGoogle Scholar
Eales, S.A., 1992. ApJ, 397, 49.CrossRefGoogle Scholar
Eales, S.A. & Rawlings, S., 1993. ApJ, 411, 67.CrossRefGoogle Scholar
Eales, S.A. et al. 1993. Nature, 363, 140.CrossRefGoogle Scholar
Eisenhardt, P. & Dickinson, M., 1992. ApJ, 399, L47.CrossRefGoogle Scholar
Falle, S.A.E.G., 1991. MNRAS, 250, 581.CrossRefGoogle Scholar
Higgins, S.W., O'Brien, T.J. & Dunlop, J.S., 1995. MNRAS, in preparation.Google Scholar
Hill, G.J. & Lilly, S.J., 1990. ApJ, 367, 1.CrossRefGoogle Scholar
Lacy, M. et al., 1995. MNRAS, in press.Google Scholar
Lilly, S.J., 1988. ApJ, 333, 161.CrossRefGoogle Scholar
Lilly, S.J., 1989. ApJ, 340, 77.CrossRefGoogle Scholar
Liu, R. & Pooley, G., 1991. MNRAS, 249, 343.CrossRefGoogle Scholar
Lonsdale, C.J. & Barthel, P.D., 1986. ApJ, 303, 617.CrossRefGoogle Scholar
McCarthy, P.J. et al. 1987. ApJ, 321, L29.CrossRefGoogle Scholar
McCarthy, P.J., van Breugel, W. & Kapahi, V.K., 1991. ApJ, 371, 478.CrossRefGoogle Scholar
McCarthy, P.J., Persson, S.E. & West, S.C., 1992. ApJ, 386, 52.CrossRefGoogle Scholar
Miley, G.K. et al. 1992. ApJ, 401, L69.CrossRefGoogle Scholar
Rees, M.J., 1989. MNRAS, 239, 1P.CrossRefGoogle Scholar
Rigler, M.A. et al. 1992. ApJ, 385, 61.CrossRefGoogle Scholar
Rottgering, H., 1993. , University of Leiden.Google Scholar
Sanders, R.H. & Prendergast, K.H., 1974. ApJ, 188, 489.CrossRefGoogle Scholar
van Albada, G.D., van Leer, B. & Roberts, W.W., 1982. A&A, 108, 76.Google Scholar
Williams, A.G., 1985. , University of Cambridge.Google Scholar
Yates, M.G., Miller, L. & Peacock, J.A., 1989. MNRAS, 240, 129.CrossRefGoogle Scholar