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Gravitationally redshifted emission implying an accretion disk and massive black hole in the active galaxy MCG–6–30–15

Nature volume 375, pages 659–661 (1995)Cite this article

Abstract

ACTIVE galactic nuclei and quasars are probably powered by the accretion of gas onto a supermassive black hole at the centre of the host galaxy1, but direct confirmation of the presence of a black hole is hard to obtain. As the gas nears the event horizon, its velocity should approach the speed of light; the resulting relativistic effects, and a gravitational redshift arising from the proximity to the black hole, should be observable, allowing us to test specific predictions of the models with the observations. Here we report the detection of these relativistic effects in an X-ray emission line (the Kα line) from ionized iron in the galaxy MCG–6–30–15. The line is extremely broad, corresponding to a velocity of ∼100,000 km s−1, and asymmetric, with most of the line flux being redshifted. These features indicate that the line most probably arises in a region between three and ten Schwarzschild radii from the centre, so that we are observing the innermost region of the accretion disk.

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References

  1. Rees, M. J. A. Rev. Astr. Astrophys. 22, 471–506 (1984).

    Article  ADS  CAS  Google Scholar 

  2. Ford, H. C. et al. Astrophys. J. L27–L30 (1994).

  3. Harmes, R. J. et al. Astrophys. J. L35–L38 (1994).

  4. Miyoshi, M. et al. Nature 373, 127–129 (1995).

    Article  ADS  CAS  Google Scholar 

  5. Pounds, K. A., Nandra, K., Stewart, G. C., George, I. M. & Fabian, A. C. Nature 344, 132–133 (1990).

    Article  ADS  Google Scholar 

  6. Nandra, K. & Pounds, K. A. Mon. Not. R. astr. Soc. 268, 405–429 (1994).

    Article  ADS  CAS  Google Scholar 

  7. Guilbert, P. W. & Rees, M. J. Mon. Not. R. astr. Soc. 233, 475–484 (1994).

    Article  ADS  Google Scholar 

  8. Lightman, A. P. & White, T. R. Astrophys. J. 335, 57–66 (1988).

    Article  ADS  Google Scholar 

  9. Fabian, A. C., Rees, M. J., Stella, L. & White, N. E. Mon. Not. R. astr. Soc. 238, 729–736 (1989).

    Article  ADS  CAS  Google Scholar 

  10. George, I. M. & Fabian, A. C. Mon. Not. R. astr. Soc. 249, 352–367 (1991).

    Article  ADS  CAS  Google Scholar 

  11. Matt, G., Perola, G. C. & Piro, L. Astr. Astrophys. 245, 75 (1991).

    Google Scholar 

  12. Matt, G., Perola, G. C., Piro, L. & Stella, L. Astr. Astrophys. 257, 63 (1992).

    ADS  CAS  Google Scholar 

  13. Laor, A. Astrophys. J. 376, 90–94 (1991).

    Article  ADS  CAS  Google Scholar 

  14. Fabian, A. C. et al. Publs astr. Soc. Japan 46, L59–L64 (1994).

    ADS  CAS  Google Scholar 

  15. Mushotzky, R. F. et al. Mon. Not. R. astr. Soc. 272, L9–L12 (1995).

    Article  ADS  CAS  Google Scholar 

  16. Chen, K., Halpern, J. P. & Filippenko, A. V. Astrophys. J. 339, 742–751 (1989).

    Article  ADS  Google Scholar 

  17. Tanaka, Y., Inoue, H. & Holt, S. S. Publs astr. Soc. Japan 46, L37–L41 (1994).

    ADS  CAS  Google Scholar 

  18. Halpern, J. P. Astrophys. J. 281, 90–94 (1984).

    Article  ADS  CAS  Google Scholar 

  19. Nandra, K., Pounds, K. A. & Stewart, G. C. Mon. Not. R. astr. Soc. 242, 660–668 (1990).

    Article  ADS  CAS  Google Scholar 

  20. Nandra, K. & Pounds, K. A. Nature 359, 215–216 (1992).

    Article  ADS  CAS  Google Scholar 

  21. Czerny, B., Zbyszewska, M. & Raine, D. J. in Iron Line Diagnostics in X-ray Sources (ed. Treves, A.) 226–229 (Springer, Berlin, 1991).

    Book  Google Scholar 

  22. Zdziarski, A. A., Johnson, W. N., Done, C., Smith, D. & McNaron-Brown, K. Astrophys. J. 438, L63–L66 (1995).

    Article  ADS  Google Scholar 

  23. Reynolds, C. S., Fabian, A. C. & Inoue, H. Mon. Not. R. astr. Soc. (submitted).

  24. Krolik, J. H. & Kallman, T. R. Astrophys. J. 320, L5–L8 (1987).

    Article  ADS  CAS  Google Scholar 

  25. Ghisellini, G., Haardt, F. & Matt, G. Mon. Not. R. astr. Soc. 267, 743–754 (1994).

    Article  ADS  Google Scholar 

  26. Krolik, J. H., Madau, P. & Zycki, P. Astrophys. J. 420, L57–L61 (1994).

    Article  ADS  CAS  Google Scholar 

  27. Ross, R. R. & Fabian, A. C. Mon. Not. R. astr. Soc. 261, 74–82 (1993).

    Article  ADS  CAS  Google Scholar 

  28. Matt, G., Fabian, A. C. & Ross, R. Mon. Not. R. astr. Soc. 262, 179–186 (1993).

    Article  ADS  CAS  Google Scholar 

  29. Stella, L. Nature 344, 747–749 (1990).

    Article  ADS  Google Scholar 

Download references

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Authors and Affiliations

  1. Institute of Space and Astronautical Science, 3-1-1 Yoshinodai, Sagamihara, Kanagawa, 229, Japan

    Y. Tanaka, H. Inoue, C. Otani, T. Dotani, T. Kii & F. Makino

  2. Max-Planck-lnstitut fur Extraterrestrische Physik, D-85740, Garching, Germany

    Y. Tanaka

  3. Institute of Astronomy, Madingley Road, Cambridge, CB3 OHA, UK

    K. Nandra & A. C. Fabian

  4. Osaka University, Machikaneyama-cho 1-1, Osaka, Japan

    K. Hayashida

  5. Department of Astrophysics, Nagoya University, Chikusa-ku, Nagoya, 464-01, Japan

    K. Iwasawa & H. Kunieda

  6. RIKEN, Institute of Physical and Chemical Research,Hirosawa, Wako, Saitama, 351-01, Japan

    M. Matsuoka

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  1. Y. Tanaka
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  2. K. Nandra
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Tanaka, Y., Nandra, K., Fabian, A. et al. Gravitationally redshifted emission implying an accretion disk and massive black hole in the active galaxy MCG–6–30–15. Nature 375, 659–661 (1995). https://doi.org/10.1038/375659a0

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