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Feedback and environmental effects in elliptical galaxies

Published online by Cambridge University Press:  21 October 2010

Craig L. Sarazin*
Affiliation:
Department of Astronomy, University of Virginia, P.O. Box 400325, Charlottesville, VA 22904-4325, USA email: sarazin@virginia.edu
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Abstract

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The role of the environment of an elliptical galaxy on its hot interstellar gas is discussed. In general, the X-ray halos of early-type galaxies tend to be smaller and fainter in denser environments, with the exception of group-central galaxies. X-ray observations show many examples of nearby galaxies which are undergoing gas stripping. On the other hand, most bright galaxies in clusters do manage to retain small coronae of X-ray emission. Recent theoretical and observational results on the role of feedback from AGN at the centers of elliptical galaxies on their interstellar gas are reviewed. X-ray observations show many examples of X-ray holes in the central regions of brightest-cluster galaxies; in many cases, the X-ray holes are filled with radio lobes. Similar radio bubbles are seen in groups and individual early-type galaxies. “Ghost bubbles” are often seen at larger radii in clusters and galaxies; these bubbles are faint in high radio frequencies, and are believed to be old radio bubbles which have risen buoyantly in the hot gas. Low frequency radio observations show that many of the ghost bubbles have radio emission; in general, these long wavelength observations show that radio sources are much larger and involve greater energies than had been previously thought. The radio bubbles can be used to estimate the total energy output of the radio jets. The total energies deposited by radio jets exceed the losses from the gas due to radiative cooling, indicating that radio sources are energetically capable of heating the cooling core gas and preventing rapid cooling.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2010

References

Blanton, E. L., Sarazin, C. L., McNamara, B. R., & Wise, M. W. 2001, ApJ 558, L15CrossRefGoogle Scholar
Blanton, E. L. et al. 2009, ApJ 697, L95Google Scholar
Brown, B. A. & Bregman, J. N. 2000, ApJ 539, 592CrossRefGoogle Scholar
Clarke, T. E. et al. 2009 ApJ 625, 748Google Scholar
Clarke, T. E. et al. 2009 ApJ 697, 481Google Scholar
Dunn, R. J. H. & Fabian, A. C. 2006, MNRAS 373, 959Google Scholar
Fabian, A. C. et al. 2006, MNRAS 366, 417Google Scholar
Jeltema, T. E., Binder, B., & Mulchaey, J. S. 2008, ApJ 679, 1162Google Scholar
Machacek, M., Nulsen, P. E. J., Jones, C., & Forman, W. R. 2006 ApJ 648, 947CrossRefGoogle Scholar
O'Sullivan, E., Forbes, D. A., & Ponman, T. J. 2001, MNRAS 328, 461Google Scholar
Randall, S. et al. 2008, ApJ 688, 208Google Scholar
Rafferty, D., McNamara, B. R., Nulsen, P. E. J., & Wise, M. W. 2006, ApJ 652, 216Google Scholar
Sun, M., Jones, C., Forman, W., Vikhlinin, A., Donahue, M., & Voit, M. 2007, ApJ 657, 197Google Scholar
White, R. E. III & Sarazin, C. L. 1991, ApJ 367, 476Google Scholar