Resonant motions of supermassive black hole triples

Wei Hao, Rainer Spurzem, Thorsten Naab, Long Wang, M. B N Kouwenhoven, Pau Amaro-Seoane, Rosemary Mardling

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearch


Triple supermassive black holes (SMBH) can form during the hierarchical mergers of massive galaxies with an existing binary. Perturbations by a third black hole may accelerate the merging process of an inner binary, for example through the Kozai mechanism. We analyze the evolution of simulated hierarchical triple SMBHs in galactic centers, and find resonances in the evolution of the semi-major axis, the eccentricity and the inclination, for both the inner and the outer orbits of the triple system, which are not only Kozai like. Through resonant oscillations, SMBH can trigger a significant increase of the inner SMBH binary eccentricity shortening the merger timescale expected from gravitational wave (GW) emission. As hierarchical triple SMBHs may be frequent in massive galaxies, the influence of orbital resonances is of great importance to our understanding of black hole coalescence and gravitational wave detection. Although Kozai mechanism is believed to play an important role in this process, detailed studies on the pattern of these resonances is necessary.

Original languageEnglish
Title of host publicationProceedings of the International Astronomical Union
Subtitle of host publicationStar Clusters and Black Holes in Galaxies across Cosmic Time
EditorsY Meiron, S Li, F K Liu, R Spurzem
Place of PublicationCambridge UK
PublisherCambridge University Press
Number of pages4
ISBN (Print)9781107078727
Publication statusPublished - 2016
EventInternational Astronomical Union Symposium 2014: Star clusters and black holes in galaxies across cosmic time - Zhongguancun Crowne Plaza Hotel, Beijing, China
Duration: 25 Aug 201429 Aug 2014
Conference number: 312th

Publication series

NameIAU Symposium Proceedings Series
PublisherCambridge University Press
ISSN (Print)1743-9213


ConferenceInternational Astronomical Union Symposium 2014
Abbreviated titleIAU Sympoisum 2014
Internet address


  • black hole physics
  • kinematics and dynamics
  • oscillations

Cite this