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Unexpectedly high formation rate of merging binary black holes in open clusters

Published online by Cambridge University Press:  11 March 2020

Jun Kumamoto Open the ORCID record for Jun Kumamoto [Opens in a new window] ,
Michiko S. Fujii Open the ORCID record for Michiko S. Fujii [Opens in a new window]  and
Ataru Tanikawa
Jun Kumamoto
Affiliation:
Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo113-0033, Japan
Michiko S. Fujii
Affiliation:
Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo113-0033, Japan
Ataru Tanikawa
Affiliation:
Department of Earth Science and Astronomy, College of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo153-8902, Japan RIKEN Center for Computational Science, 7-1-26 Minatojima-minami-machi, Chuo-ku, Kobe, Hyogo650-0047, Japan
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Abstract

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Gravitational wave direct detections suggest that 30 M⊙ binary black holes (BBHs) commonly exist in the universe. One possible formation scenario of such BBHs is dynamical three-body encounters in dense star clusters. We performed a series of direct N-body simulations with a mass of 2500 and 10000 M⊙ and found a new channel for the formation of BBHs which is dominant in open clusters. In open clusters, the core-collapse time is shorter than in globular clusters, and therefore massive main-sequence (MS) binaries can form before they evolve to BHs. These MS binaries experience common envelope evolution and evolve to hard BBHs, which can merge within the Hubble time. The number of BBH mergers per unit mass obtained from our simulations reached 20–50 % of that for globular clusters, assuming an initial cluster mass function. Thus, open clusters can be a dominant formation site of hard BBHs.

Keywords

gravitational wavesmethods: numericalopen clusters and associations: general
Type
Contributed Papers
Information
Proceedings of the International Astronomical Union , Volume 14 , Symposium S351: Star Clusters: From the Milky Way to the Early Universe , May 2019 , pp. 204 - 207
Copyright
© International Astronomical Union 2020

References

Abbott, B. P., Abbott, R., Abbott, T. D., Abernathy, M. R.Acernese, F., Ackley, K., Adams, C., Adams, T., Addesso, P., Adhikari, R. X., et al. 2016, Physical Review Letters, 116, 061102CrossRefGoogle Scholar
Belczynski, K., Holz, D. E., Bulik, T., & O’Shaughnessy, R. 2016, Nature, 534, 512CrossRefGoogle Scholar
Di Carlo, U. N., Giacobbo, N, Mapelli, M., Pasquato, M., Spera, M., Wang, L., & Haardt, F. 2019, MNRAS, 487, 2947CrossRefGoogle Scholar
Fujii, M. S., Tanikawa, A., & Makino, J. 2017, PASJ, 69, 94CrossRefGoogle Scholar
Hurley, J. R., Pols, O. R., & Tout, C. A. 2000, MNRAS, 315, 543CrossRefGoogle Scholar
Kinugawa, T., Inayoshi, K., Hotokezaka, K., Nakauchi, D., & Nakamura, T. 2014, MNRAS, 442, 2963CrossRefGoogle Scholar
Kroupa, P. 2001, MNRAS, 322, 231CrossRefGoogle Scholar
Kumamoto, J., Fujii, M. S., & Tanikawa, A. 2019, MNRAS, 486, 3942CrossRefGoogle Scholar
Peters, P. C. & Mathews, J. 1963, Physical Review, 131, 435CrossRefGoogle Scholar
Portegies Zwart, S. F. & McMillan, S. L. W. 2000, ApJL, 528, L17CrossRefGoogle Scholar
Portegies Zwart, S. F., McMillan, S. L. W., & Gieles, M. 2010, ARAA, 48, 431CrossRefGoogle Scholar
Rodriguez, C. L., Morscher, M., Wang, L., Chatterjee, S., Rasio, F. A., & Spurzem, R. 2016, MNRAS, 463, 2109CrossRefGoogle Scholar
Tanikawa, A. 2013, MNRAS, 435, 1358CrossRefGoogle Scholar
Wang, L., Spurzem, R., Aarseth, S., Nitadori, K., Berczik, P., Kouwenhoven, M. B. N., & Naab, T. 2015, MNRAS, 450, 4070CrossRefGoogle Scholar
Ziosi, B. M., Mapelli, M., Branchesi, M., & Tormen, G. 2014, MNRAS, 441, 3703CrossRefGoogle Scholar