Hot bubbles from active galactic nuclei as a heat source in cooling-flow clusters

Abstract

Hot, X-ray-emitting plasma permeates clusters of galaxies. The X-ray surface brightness often shows a peak near the centre of the cluster that is coincident with a drop in the entropy of the gas. This has been taken as evidence for a ‘cooling flow’, where the gas cools by radiating away its energy, and then falls to the centre1. Searches for this cool gas have revealed significantly less than predicted2, indicating that the mass deposition rate is much lower than expected. Most clusters with cooling flows, however, also host an active galactic nucleus at their centres3. These active galactic nuclei can inflate large bubbles of hot plasma that subsequently rise through the cluster ‘atmosphere’, thus stirring the cooling gas4,5 and adding energy. Here we report highly resolved hydrodynamic simulations which show that buoyant bubbles increase the cooling time in the inner regions of clusters and significantly reduce the deposition of cold gas.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Figure 1: Snapshots of the density at two different times in our simulation (run 2).
Figure 2: Average specific entropy of the ambient material in units of 3.1 × 1027 erg cm2 g-5/3 at different heights.
Figure 3: Cooling time of the ambient material averaged over horizontal slices.

References

  1. 1

    Fabian, A. C. Cooling flows in clusters of galaxies. Annu. Rev. Astron. Astrophys. 32, 277–318 (1994)

    ADS  Article  Google Scholar 

  2. 2

    Böhringer, H., Matsushita, K., Churazov, E., Ikebe, Y. & Chen, Y. The new emerging model for the structure of cooling cores in clusters of galaxies. Astron. Astrophys. (submitted); preprint astro-ph/0111112 at 〈http://xxx.lanl.gov〉 (2001)

  3. 3

    Burns, J. O. The radio properties of cD galaxies in Abell clusters. I – an X-ray selected sample. Astron. J. 99, 14–30 (1990)

    ADS  CAS  Article  Google Scholar 

  4. 4

    Churazov, E., Forman, W., Jones, C. & Böhringer, H. Asymmetric, arc minute scale structures around NGC 1275. Astron. Astrophys. 356, 788–794 (2000)

    ADS  Google Scholar 

  5. 5

    Churazov, E., Brüggen, M., Kaiser, C. R., Böhringer, H. & Forman, W. Evolution of buoyant bubbles in M87. Astrophys. J. 554, 261–794 (2001)

    ADS  Article  Google Scholar 

  6. 6

    Voit, G. M. & Bryan, G. L. Regulation of the X-ray luminosity of clusters of galaxies by cooling and supernova feedback. Nature 414, 425–427 (2001)

    ADS  CAS  Article  Google Scholar 

  7. 7

    Wu, K. K. S., Fabian, A. C. & Nulsen, P. E. J. Non-gravitational heating in the hierarchical formation of X-ray clusters. Mon. Not. R. Astron. Soc. 318, 889–912 (2000)

    ADS  Article  Google Scholar 

  8. 8

    Heinz, S., Reynolds, C. S. & Begelman, M. C. X-ray signatures of evolving radio galaxies. Astrophys. J. 501, 126–136 (1998)

    ADS  Article  Google Scholar 

  9. 9

    Kaiser, C. R. & Alexander, P. Heating of the intergalactic medium by FRII radio sources. Mon. Not. R. Astron. Soc. 305, 707–723 (1999)

    ADS  Article  Google Scholar 

  10. 10

    Reynolds, C. S., Heinz, S. & Begelman, M. C. The hydrodynamics of dead radio galaxies. Mon. Not. R. Astron. Soc. (in the press)

  11. 11

    Fabian, A. C. et al. Chandra imaging of the complex X-ray core of the Perseus cluster. Mon. Not. R. Astron. Soc. 318, L65–L68 (2000)

    ADS  Article  Google Scholar 

  12. 12

    Brüggen, M. & Kaiser, C. R. Buoyant radio plasma in clusters of galaxies. Mon. Not. R. Astron. Soc. 325, 676–684 (2001)

    ADS  Article  Google Scholar 

  13. 13

    McNamara, B. R. et al. Discovery of ghost cavities in Abell 2597's X-ray atmosphere. Astrophys. J. (submitted); preprint astro-ph/0110554 at 〈http://xxx.lanl.gov〉 (2001)

  14. 14

    Brüggen, M., Kaiser, C. R., Churazov, E. & Ensslin, T. A. Simulation of radio plasma in clusters of galaxies. Mon. Not. R. Astron. Soc. (in the press)

  15. 15

    Quilis, V., Bower, R. G. & Balogh, M. Bubbles, feedback and the intra-cluster medium: Three-dimensional hydrodynamic simulations. Mon. Not. R. Astron. Soc. 328, 1091–1097 (2001)

    ADS  Article  Google Scholar 

  16. 16

    Fryxell, B. et al. FLASH: An adaptive mesh hydrodynamics code for modeling thermonuclear flashes. Astrophys. J. Suppl. 131, 273–334 (2000)

    ADS  CAS  Article  Google Scholar 

  17. 17

    Nulsen, P. E. J. & Böhringer, H. A ROSAT determination of the central mass of the Virgo cluster. Mon. Not. R. Astron. Soc. 274, 1093–1106 (1995)

    ADS  Google Scholar 

  18. 18

    Binney, J. & Tabor, G. Evolving cooling flows. Mon. Not. R. Astron. Soc. 276, 663–678 (1995)

    ADS  Article  Google Scholar 

  19. 19

    Soker, N., White, R. E., David, L. P. & McNamara, B. R. A moderate cluster cooling flow model. Astrophys. J. 549, 832–839 (2001)

    ADS  Article  Google Scholar 

Download references

Acknowledgements

The computations reported here were performed using the UK Astrophysical Fluids Facility (UKAFF). The software used in this work was in part developed by the DOE supported ASCI/Alliances Center for Thermonuclear Flashes at the University of Chicago.

Author information

Affiliations

Authors

Corresponding author

Correspondence to Marcus Brüggen.

Ethics declarations

Competing interests

The authors declare that they have no competing financial interests.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Brüggen, M., Kaiser, C. Hot bubbles from active galactic nuclei as a heat source in cooling-flow clusters. Nature 418, 301–303 (2002). https://doi.org/10.1038/nature00857

Download citation

Further reading

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.