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H2O maser emission from the Seyfert 2 galaxy IC 2560: evidence for a super-massive black hole and a probe for mass-accretion rate

Published online by Cambridge University Press:  03 August 2017

Yuko Ishihara ,
Naomasa Nakai ,
Naoko Iyomoto ,
Kazuo Makishima ,
Phil Diamond  and
Peter Hall
Yuko Ishihara
Affiliation:
Nobeyama Radio Observatory, Minamimaki Minamisaku, Nagano 384-1305, Japan
Naomasa Nakai
Affiliation:
Nobeyama Radio Observatory, Minamimaki Minamisaku, Nagano 384-1305, Japan
Naoko Iyomoto
Affiliation:
Department of Physics, The University of Tokyo, 7-3-1 Hongo Bunkyo, Tokyo 113-0033, Japan
Kazuo Makishima
Affiliation:
Department of Physics, The University of Tokyo, 7-3-1 Hongo Bunkyo, Tokyo 113-0033, Japan
Phil Diamond
Affiliation:
Jodrell Bank Observatory, University of Manchester, Macclesfield, Cheshire SK11 9DL, UK
Peter Hall
Affiliation:
Australia Telescope National Facility, CSIRO, PO Box 76 Epping, NSW 1710, Australia

Abstract

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Our observations of H2O masers have detected some high-velocity features and a secular velocity drift of the systemic features in the Seyfert 2 Galaxy IC 2560. The high-velocity features were blue- and red-shifted from the systemic velocity of 220-420 km s−1 and 210-350 km s−1, respectively. The velocity of the systemic features drifted at a secular rate of 2.62 km s−1 yr−1. Assuming the existence of a compact rotating disk as in NGC 4258, IC 2560 possesses a nuclear disk with inner and outer radii of 0.07 pc and 0.26 pc, respectively, and a confined mass of 2.8 × 106M⊙ at the center, making the central density > 2.1 × 109M⊙ pc−3. Such a dense object cannot be a cluster of stars, and this strongly suggests that the central mass is a super-massive black hole. Since the 2-10 keV luminosity of IC 2560 is 1 × 1041 erg s−1, the mass accretion rate of the suggested black hole must be 2 × 10−5M⊙ yr−1.

Type
Part 5. Extragalactic Nuclear Masers
Information
Symposium - International Astronomical Union , Volume 206: Cosmic Masers: From Protostars to Blackholes , 2002 , pp. 400 - 403
Copyright
Copyright © Astronomical Society of the Pacific 2002 

References

Aaronson, M., Bothun, G. D., Cornell, M. E., Dawe, J. A., Dickens, R. J., Hall, P. J., Sheng, H. M., Huchra, J. P., Lucey, J. R., Mould, J. R., Murray, J. D., Schommer, R. A., & Wright, A. E. 1989, ApJ, 338, 654 Google Scholar
Braatz, J. A., Wilson, A. S., & Henkel, C. 1996, ApJS, 106, 51 Google Scholar
de Vaucouleurs, G., de Vaucouleurs, A., Corwin, H. G. Jr, Buta, R., Paturel, G., & Fouqué, P. 1991, Third Reference Catalogue of Bright Galaxies (New York, Springer-Verlag)Google Scholar
Ishihara, Y., Nakai, N., Iyomoto, N., Makishima, K., Diamond, P., & Hall, P. 2001, to apper in PASJ Google Scholar
Maoz, E. 1998, ApJ, 494, L181 Google Scholar
Miyoshi, M., Moran, J., Herrnstein, J., Greenhill, L., Nakai, N., Diamond, P., & Inoue, M. 1995, Nature, 373, 127 Google Scholar
Nakai, N., Inoue, M., & Miyoshi, M. 1993, Nature, 361, 45 CrossRefGoogle Scholar
Nakai, N., Inoue, M., Miyazawa, K., Miyoshi, M., & Hall, P. 1995, PASJ, 47, 771 Google Scholar
Strauss, M. A., Huchra, J. P., Davis, M., Yahil, A., Fisher, K. B., & Tonry, J. 1992, ApJS, 83, 29 Google Scholar
Wilson, A. S., Braatz, J. A., & Henkel, C. 1995, ApJ, 455, L127 Google Scholar