Efficient Merger of Binary Supermassive Black Holes in Nonaxisymmetric Galaxies

By Peter Berczik, D. Merritt, Rainer Spurzem, Hans-Peter Bischof. 2006

229 citations recorded by the source corpus.

Binary supermassive black holes (SBHs) form naturally in galaxy mergers, but their long-term evolution is uncertain. In spherical galaxies, N-body simulations show that binary evolution stalls at separations much too large for significant emission of gravitational waves (the "final-parsec problem"). Here we follow the long-term evolution of a massive binary in more realistic, triaxial and rotating galaxy models with particle numbers as high as 106. We find that the binary does not stall. The binary hardening rates that we observe are sufficient to allow complete coalescence of binary SBHs in 10 Gyr or less, even in the absence of collisional loss-cone refilling or gasdynamical torques, thus providing a potential solution to the final-parsec problem.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/797dc88624ee88921fd8acd87effe67c270d5c77

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Citations in the corpus

Massive Perturber-driven Interactions between Stars and a Massive Black Hole (2006, background): “…the aim of explaining various open questions (e.g. the stalling problem of MBH binary coalescence, Berczik et al. (2005); Merritt & Wang (2005); Berczik et al. (2006), or MBH feeding, Zhao et al. 2002; Miralda-Escudé & Kollmeier 2005) or in the hope that they may lead to significantly higher…”
Dynamics of triple black hole systems in hierarchically merging massive galaxies (2006, background): “…is probably a necessary prerequisite for the survival of the inner binary for of order a Hubble time until the next merger (Merritt & Poon 2004; Berczik et al. 2006), the parameters r1, ..., r4 were chosen to give a spherical profile near the galactic center, and axis ratios approaching 1.3…”
Mass Deficits, Stalling Radii, and the Merger Histories of Elliptical Galaxies (2006, unknown): “Nevertheless, the binary need not stall (Berczik et al. 2006).”
Doing Science with eLISA: Astrophysics and Cosmology in the Millihertz Regime (2012, background): “Self-consistent high resolution direct N-body simulations (Berczik et al., 2006, Khan et al., 2011, Preto et al., 2011) indicate that the stellar potential of the remnant galaxy retains, in response to the anisotropy of the merger, a sufficiently high degree of rotation and triaxiality to guarantee…”
EFFICIENT MERGER OF BINARY SUPERMASSIVE BLACK HOLES IN MERGING GALAXIES (2011, background): “Similar N -dependence has been seen in other studies of binary evolution in spherical galaxies (e.g. Makino & Funato 2004; Berczik et al. 2006; Merritt et al. 2007).”
The NANOGrav 15 yr Data Set: Constraints on Supermassive Black Hole Binaries from the Gravitational-wave Background (2023, background): “However, this so-called “final-parsec problem” has a number of potential theoretical solutions (e.g., Berczik et al. 2006; Holley-Bockelmann & Sigurdsson 2006; Khan et al. 2011; Holley-Bockelmann & Khan 2015).”
A LARGE SYSTEMATIC SEARCH FOR CLOSE SUPERMASSIVE BINARY AND RAPIDLY RECOILING BLACK HOLES (2011, unknown): “However, it is still unknown whether this replenishment is possible via stellar dynamical processes (see, for example, discussions in Milosavljević & Merritt 2003; Berczik et al. 2006; Sesana, Haardt, & Madau 2007).”
Supermassive black hole binaries in gaseous and stellar circumnuclear discs: orbital dynamics and gas accretion (2006, background): “…in spherical backgrounds, can lead to an increase of the eccentricity, thus acting against the circularization driven by the large–scale action of the gaseous and/or stellar disc (Quinlan 1996; Aarseth 2003; Matsubayashi, Makino & Ebisuzaki 2005; Berczik et al. 2006; Sesana et al. in preparation).”
Surface brightness profile of the Milky Way’s nuclear star cluster (2014, background): “It has been claimed with direct-summation N−body integrations of galactic nuclei with an initial amount of rotation that triaxiality or axisymmetry alone drives the binary efficiently to coalescence in less than a Hubble time (Berczik et al. 2006).”
Tearing up the disc: misaligned accretion on to a binary (2013, background): “However, there is also progress with stellar dynamics; triaxial potentials repeatedly produce stellar orbits which interact with the binary, reducing the time taken to drive the merger (Berczik et al. 2006).”
THE ASSEMBLY OF SUPERMASSIVE BLACK HOLES AT HIGH REDSHIFTS (2008, background): “The second assumption is valid for binaries in extremely gas-rich environments (see Milosavljevic & Merritt 2003 for a review), or in triaxial galaxies (Berczik et al. 2006).”
The stochastic gravitational-wave background from massive black hole binary systems: implications for observations with Pulsar Timing Arrays (2008, background): “…scenario is different in axisymmetric and triaxial systems (more realistic if we consider the end-product of a merger), and there are indications (Berczik et al. 2006) that in the latter case the stellar supply to the slingshot process could be sufficient to drive binaries to coalescence within…”
The evolution of massive black holes and their spins in their galactic hosts (2012, background): “…may be replenished by star- tar encounters (Milosavljević & Merritt 2003; Yu 2002), or as aresult of the triaxial gravitational potential that one naturlly expects in galaxies forming from major mergers (Merritt & Poon 2004; Berczik et al. 2006; Khan, Just, & Merritt 2011; Preto et al. 2011).”
Massive Black Hole Binary Mergers in Dynamical Galactic Environments (2016, background): “N-Body simulations have continued to develop and improve our understanding of rotating galaxies (e.g. Berczik et al. 2006), and more realistic galaxymerger environments and galaxy shapes (e.g. Khan et al. 2011, 2013).”
THREE-DIMENSIONAL MAGNETOHYDRODYNAMIC SIMULATIONS OF CIRCUMBINARY ACCRETION DISKS: DISK STRUCTURES AND ANGULAR MOMENTUM TRANSPORT (2011, background): “Although they are potential solutions to this problem, they require either special non-axisymmetric stellar distributions (Berczik et al. 2006; Khan et al. 2011; Preto et al. 2011) or extra perturbers such as giant molecular clouds (Perets & Alexander 2008).”