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Unraveling AGN feedback and ICM physics with deep Chandra X-ray observations of the galaxy group NGC 5813

Published online by Cambridge University Press:  24 March 2015

Scott W. Randall
Affiliation:
Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA, 02138, USA email: [email protected], [email protected], [email protected], [email protected]
Paul E. J. Nulsen
Affiliation:
Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA, 02138, USA email: [email protected], [email protected], [email protected], [email protected]
Christine Jones
Affiliation:
Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA, 02138, USA email: [email protected], [email protected], [email protected], [email protected]
William R. Forman
Affiliation:
Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA, 02138, USA email: [email protected], [email protected], [email protected], [email protected]
Tracy E. Clarke
Affiliation:
Naval Research Laboratory, Code 7213, 4555 Overlook Ave SW, Washington, DC 20375, USA email: [email protected]
Elizabeth L. Blanton
Affiliation:
Astronomy Department and Institute for Astrophysical Research, Boston University, 725 Commonwealth Avenue, Boston, MA 02215, USA email: [email protected]
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Abstract

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We present results from deep Chandra X-ray observations of the galaxy group NGC 5813. This system shows three pairs of collinear cavities, with each pair associated with an elliptical AGN outburst shock. Due to the relatively regular morphology of this system, and the unique unambiguous detection of three distinct AGN outburst shocks, it is particularly well-suited for the study of AGN feedback and the AGN outburst history. We find that the mean kinetic power is roughly the same for each outburst, and that the total energy associated with the youngest outburst is significantly lower than that of the previous outbursts. This implies that the mean AGN jet power has remained stable for at least 50 Myr, and that the youngest outburst is ongoing. We find that the mean shock heating rate balances the local radiative cooling rate at each shock front, suggesting that AGN outburst shock heating alone is sufficient to offset cooling and establish AGN/ICM feedback within at least the central 30 kpc. Finally, we find non-zero shock front widths that are too large to be explained by particle diffusion, but are instead consistent with arising from broadening of the shock fronts due to propagation through a turbulent ICM with a mean turbulent speed of ~ 70 km s−1.

Type
Contributed Papers
Copyright
Copyright © International Astronomical Union 2015 

References

Bîrzan, L., Rafferty, D. A., McNamara, B. R., Wise, M. W., & Nulsen, P. E. J. 2004, ApJ, 607, 800Google Scholar
Churazov, E., Brüggen, M., Kaiser, C. R., Böhringer, H., & Forman, W. 2001, ApJ, 554, 261Google Scholar
David, L. P., Jones, C., Forman, W., et al. 2009, ApJ, 705, 624CrossRefGoogle Scholar
de Plaa, J., Werner, N., Simionescu, A., et al. 2010, A&A, 523, 81Google Scholar
Fabian, A. C. 2012, ARA&A, 50, 455Google Scholar
Hlavacek-Larrondo, J., Fabian, A. C., Edge, A. C., et al. 2012, MNRAS, 421, 1360CrossRefGoogle Scholar
Landau, L. D., & Lifshitz, E. M. 1987 Course of Theoretical Physics, Vol. 6: Fluid Mechanics (London: Pergamon)Google Scholar
Lau, E. T., Kravtsov, A. V., & Nagai, D. 2009, ApJ, 705, 1129Google Scholar
McNamara, B. R. & Nulsen, P. E. J. 2007, ARA&A, 45, 117Google Scholar
Nulsen, P. E. J., Jones, C., Forman, W. R., et al. 2007, in Heating versus Cooling in Galaxies and Clusters of Galaxies, ed. Böhringer, H., Pratt, G. W., Finoguenov, A., & Schuecker, P. (Berlin: Springer), 210Google Scholar
Nulsen, P. E. J., Li, Z., Forman, W. R., et al. 2013, ApJ, 775, 117Google Scholar
Peterson, J. R. & Fabian, A. C. 2006, PhR, 427, 1Google Scholar
Peterson, J. R., Paerels, F. B. S., Kaastra, J. S., et al. 2001, A&A, 365, L104Google Scholar
Rafferty, D. A., McNamara, B. R., Nulsen, P. E., & Wise, M. W. 2006, ApJ, 652, 216Google Scholar
Randall, S. W., Forman, W. R., Giacintucci, S., et al. 2011, ApJ, 726, 86Google Scholar
Randall, S. W.et al. 2014, in preparationGoogle Scholar
Rebusco, P., Churazov, E., Böhringer, H., & Forman, W. 2005, MNRAS, 359, 1041Google Scholar
Sanders, J. S. & Fabian, A. C. 2013, MNRAS, 429, 2727Google Scholar