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Two stellar-mass black holes in the globular cluster M22

Nature volume 490, pages 71–73 (2012)Cite this article

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Abstract

Hundreds of stellar-mass black holes probably form in a typical globular star cluster, with all but one predicted to be ejected through dynamical interactions1,2,3. Some observational support for this idea is provided by the lack of X-ray-emitting binary stars comprising one black hole and one other star (‘black-hole/X-ray binaries’) in Milky Way globular clusters, even though many neutron-star/X-ray binaries are known4. Although a few black holes have been seen in globular clusters around other galaxies5,6, the masses of these cannot be determined, and some may be intermediate-mass black holes that form through exotic mechanisms7. Here we report the presence of two flat-spectrum radio sources in the Milky Way globular cluster M22, and we argue that these objects are black holes of stellar mass (each ∼10–20 times more massive than the Sun) that are accreting matter. We find a high ratio of radio-to-X-ray flux for these black holes, consistent with the larger predicted masses of black holes in globular clusters compared to those outside8. The identification of two black holes in one cluster shows that ejection of black holes is not as efficient as predicted by most models1,2,4, and we argue that M22 may contain a total population of ∼5–100 black holes. The large core radius of M22 could arise from heating produced by the black holes9.

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Figure 1: VLA radio continuum image of the core of the globular cluster M22.
Figure 2: Optical images of M22 and the candidate companion stars to the radio sources.
Figure 3: Radio–X-ray correlation for stellar-mass black holes.

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References

  1. Kulkarni, S. R., Hut, P. & McMillan, S. Stellar black holes in globular clusters. Nature 364, 421–423 (1993)

    Article  ADS  Google Scholar 

  2. Sigurdsson, S. & Hernquist, L. Primordial black holes in globular clusters. Nature 364, 423–425 (1993)

    Article  ADS  Google Scholar 

  3. Portegies Zwart, S. F. & McMillan, S. L. W. Black hole mergers in the universe. Astrophys. J. 528, L17–L20 (2000)

    Article  ADS  Google Scholar 

  4. Kalogera, V., King, A. R. & Rasio, F. A. Could black hole X-ray binaries be detected in globular clusters? Astrophys. J. 601, L171–L174 (2004)

    Article  ADS  CAS  Google Scholar 

  5. Maccarone, T. J., Kundu, A., Zepf, S. E. & Rhode, K. L. A black hole in a globular cluster. Nature 445, 183–185 (2007)

    Article  ADS  CAS  Google Scholar 

  6. Irwin, J. A., Brink, T. G., Bregman, J. N. & Roberts, T. P. Evidence for a stellar disruption by an intermediate-mass black hole in an extragalactic globular cluster. Astrophys. J. 712, L1–L4 (2010)

    Article  ADS  CAS  Google Scholar 

  7. Portegies Zwart, S. F., Baumgardt, H., Hut, P., Makino, J. & McMillan, S. L. W. Formation of massive black holes through runaway collisions in dense young star clusters. Nature 428, 724–726 (2004)

    Article  ADS  Google Scholar 

  8. Belczynski, K. et al. On the maximum mass of stellar black holes. Astrophys. J. 714, 1217–1226 (2010)

    Article  ADS  Google Scholar 

  9. Mackey, A. D., Wilkinson, M. I., Davies, M. B. & Gilmore, G. F. Black holes and core expansion in massive star clusters. Mon. Not. R. Astron. Soc. 386, 65–95 (2008)

    Article  ADS  Google Scholar 

  10. Strader, J. et al. No evidence for intermediate-mass black holes in globular clusters: strong constraints from the VLA. Astrophys. J. 750, L27 (2012)

    Article  ADS  Google Scholar 

  11. McLaughlin, D. & van der Marel, R. Resolved massive star clusters in the Milky Way and its satellites: brightness profiles and a catalog of fundamental parameters. Astrophys. J. Suppl. Ser. 161, 304–360 (2005)

    Article  ADS  CAS  Google Scholar 

  12. Monaco, L., Pancino, E., Ferraro, F. R. & Bellazzini, M. Wide-field photometry of the Galactic globular cluster M22. Mon. Not. R. Astron. Soc. 349, 1278–1290 (2004)

    Article  ADS  Google Scholar 

  13. Maccarone, T. & Knigge, C. Compact objects in globular clusters. Astron. Geophys. 48, 5.12–5.20 (2007)

    ADS  Google Scholar 

  14. Gallo, E., Fender, R. P. & Hynes, R. I. The radio spectrum of a quiescent stellar mass black hole. Mon. Not. R. Astron. Soc. 356, 1017–1021 (2005)

    Article  ADS  CAS  Google Scholar 

  15. Anderson, J. et al. The ACS survey of Galactic globular clusters. V. Generating a comprehensive star catalog for each cluster. Astron. J. 135, 2055–2073 (2008)

    Article  ADS  Google Scholar 

  16. Maccarone, T. J. Do X-ray binary spectral state transition luminosities vary? Astron. Astrophys. 409, 697–706 (2003)

    Article  ADS  Google Scholar 

  17. Gallo, E., Fender, R. P. & Pooley, G. G. A universal radio-X-ray correlation in low/hard state black hole binaries. Mon. Not. R. Astron. Soc. 344, 60–72 (2003)

    Article  ADS  Google Scholar 

  18. Gallo, E. et al. A radio-emitting outflow in the quiescent state of A0620–00: implications for modelling low-luminosity black hole binaries. Mon. Not. R. Astron. Soc. 370, 1351–1360 (2006)

    Article  ADS  CAS  Google Scholar 

  19. Miller-Jones, J. C. A., Jonker, P. G., Maccarone, T. J., Nelemans, G. & Calvelo, D. E. A deep radio survey of hard state and quiescent black hole X-Ray binaries. Astrophys. J. 739, L18 (2011)

    Article  ADS  Google Scholar 

  20. Miller-Jones, J. C. A. et al. Zooming in on a sleeping giant: milliarcsecond High Sensitivity Array imaging of the black hole binary V404 Cyg in quiescence. Mon. Not. R. Astron. Soc. 388, 1751–1758 (2008)

    ADS  CAS  Google Scholar 

  21. Corbel, S., Tomsick, J. A. & Kaaret, P. On the origin of black hole X-Ray emission in quiescence: Chandra observations of XTE J1550–564 and H1743–322. Astrophys. J. 636, 971–978 (2006)

    Article  ADS  Google Scholar 

  22. Merloni, A., Heinz, S. & di Matteo, T. A fundamental plane of black hole activity. Mon. Not. R. Astron. Soc. 345, 1057–1076 (2003)

    Article  ADS  Google Scholar 

  23. Remillard, R. A. & McClintock, J. E. X-ray properties of black-hole binaries. Annu. Rev. Astron. Astrophys. 44, 49–92 (2006)

    Article  ADS  Google Scholar 

  24. Tauris, T. M. & van den Heuvel, E. P. J. in Compact Stellar X-ray Sources (eds Lewin, W. H. G. & van der Klis, M. ) 623–665 (Cambridge Univ. Press, 2006)

    Book  Google Scholar 

  25. Ivanova, N. et al. Formation of black hole X-ray binaries in globular clusters. Astrophys. J. 717, 948–957 (2010)

    Article  ADS  Google Scholar 

  26. Repetto, S., Davies, M. B. & Sigurdsson, S. Investigating stellar-mass black hole kicks. Mon. Not. R. Astron. Soc. (in the press); preprint at http://arXiv.org/abs/1203.3077 (2012)

  27. Lynch, R. S., Ransom, S. M., Freire, P. C. C. & Stairs, I. H. Six new recycled globular cluster pulsars discovered with the Green Bank Telescope. Astrophys. J. 734, 89 (2011)

    Article  ADS  Google Scholar 

  28. Migliari, S. & Fender, R. P. Jets in neutron star X-ray binaries: a comparison with black holes. Mon. Not. R. Astron. Soc. 366, 79–91 (2006)

    Article  ADS  Google Scholar 

  29. Körding, E. G., Knigge, C., Tzioumis, T. & Fender, R. Detection of radio emission from a nova-like cataclysmic variable: evidence of jets? Mon. Not. R. Astron. Soc. 418, L129–L132 (2011)

    Article  ADS  Google Scholar 

Download references

Acknowledgements

The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc. L.C. is a Jansky Fellow of the National Radio Astronomy Observatory. This work is partially based on observations made with the NASA/ESA Hubble Space Telescope, and obtained from the Hubble Legacy Archive, which is a collaboration between the Space Telescope Science Institute (STScI/NASA), the Space Telescope European Coordinating Facility (ST-ECF/ESA) and the Canadian Astronomy Data Centre (CADC/NRC/CSA).

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Authors and Affiliations

  1. Department of Physics and Astronomy, Michigan State University, East Lansing, 48824, Michigan, USA

    Jay Strader & Laura Chomiuk

  2. Harvard-Smithsonian Center for Astrophysics, Cambridge, 02138, Massachusetts, USA

    Jay Strader & Laura Chomiuk

  3. National Radio Astronomy Observatory, PO Box O, Socorro, 87801, New Mexico, USA

    Laura Chomiuk

  4. School of Physics and Astronomy, University of Southampton, Highfield SO17 IBJ, UK,

    Thomas J. Maccarone

  5. International Centre for Radio Astronomy Research, Curtin University, GPO Box U1987, Perth, Western Australia 6845, Australia,

    James C. A. Miller-Jones

  6. Department of Physics and Astronomy, University of Utah, Salt Lake City, Utah 84112, USA,

    Anil C. Seth

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Contributions

J.S. wrote the text. L.C. reduced the data. All authors contributed to the interpretation of the data and commented on the final manuscript.

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Correspondence to Jay Strader.

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The authors declare no competing financial interests.

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Strader, J., Chomiuk, L., Maccarone, T. et al. Two stellar-mass black holes in the globular cluster M22. Nature 490, 71–73 (2012). https://doi.org/10.1038/nature11490

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