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Title: Lidov–Kozai Cycles with Gravitational Radiation: Merging Black Holes in Isolated Triple Systems

Abstract

We show that a black-hole binary with an external companion can undergo Lidov–Kozai cycles that cause a close pericenter passage, leading to a rapid merger due to gravitational-wave emission. This scenario occurs most often for systems in which the companion has a mass comparable to the reduced mass of the binary and the companion orbit has a semimajor axis within a factor of ∼10 of the binary semimajor axis. Using a simple population-synthesis model and three-body simulations, we estimate the rate of mergers in triple black-hole systems in the field to be about six per Gpc{sup 3} per year in the absence of natal kicks during black-hole formation. This value is within the low end of the 90% credible interval for the total black hole–black hole merger rate inferred from the current LIGO results. There are many uncertainties in these calculations, the largest of which is the unknown distribution of natal kicks. Even modest natal kicks of 40 km s{sup −1} will reduce the merger rate by a factor of 40. A few percent of these systems will have eccentricity greater than 0.999 when they first enter the frequency band detectable by aLIGO (above 10 Hz).

Authors:
 [1];  [2]
  1. Department of Astrophysical Sciences, Princeton University, Ivy Lane, Princeton, NJ 08544 (United States)
  2. Institute for Advanced Study, 1 Einstein Drive Princeton, NJ 08540 (United States)
Publication Date:
OSTI Identifier:
22663871
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 836; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BLACK HOLES; COMPARATIVE EVALUATIONS; DISTRIBUTION; EMISSION; GRAVITATIONAL RADIATION; GRAVITATIONAL WAVES; MASS; SIMULATION; STARS; SYNTHESIS; THREE-BODY PROBLEM

Citation Formats

Silsbee, Kedron, and Tremaine, Scott, E-mail: ksilsbee@astro.princeton.edu, E-mail: tremaine@ias.edu. Lidov–Kozai Cycles with Gravitational Radiation: Merging Black Holes in Isolated Triple Systems. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA5729.
Silsbee, Kedron, & Tremaine, Scott, E-mail: ksilsbee@astro.princeton.edu, E-mail: tremaine@ias.edu. Lidov–Kozai Cycles with Gravitational Radiation: Merging Black Holes in Isolated Triple Systems. United States. doi:10.3847/1538-4357/AA5729.
Silsbee, Kedron, and Tremaine, Scott, E-mail: ksilsbee@astro.princeton.edu, E-mail: tremaine@ias.edu. Fri . "Lidov–Kozai Cycles with Gravitational Radiation: Merging Black Holes in Isolated Triple Systems". United States. doi:10.3847/1538-4357/AA5729.
@article{osti_22663871,
title = {Lidov–Kozai Cycles with Gravitational Radiation: Merging Black Holes in Isolated Triple Systems},
author = {Silsbee, Kedron and Tremaine, Scott, E-mail: ksilsbee@astro.princeton.edu, E-mail: tremaine@ias.edu},
abstractNote = {We show that a black-hole binary with an external companion can undergo Lidov–Kozai cycles that cause a close pericenter passage, leading to a rapid merger due to gravitational-wave emission. This scenario occurs most often for systems in which the companion has a mass comparable to the reduced mass of the binary and the companion orbit has a semimajor axis within a factor of ∼10 of the binary semimajor axis. Using a simple population-synthesis model and three-body simulations, we estimate the rate of mergers in triple black-hole systems in the field to be about six per Gpc{sup 3} per year in the absence of natal kicks during black-hole formation. This value is within the low end of the 90% credible interval for the total black hole–black hole merger rate inferred from the current LIGO results. There are many uncertainties in these calculations, the largest of which is the unknown distribution of natal kicks. Even modest natal kicks of 40 km s{sup −1} will reduce the merger rate by a factor of 40. A few percent of these systems will have eccentricity greater than 0.999 when they first enter the frequency band detectable by aLIGO (above 10 Hz).},
doi = {10.3847/1538-4357/AA5729},
journal = {Astrophysical Journal},
number = 1,
volume = 836,
place = {United States},
year = {Fri Feb 10 00:00:00 EST 2017},
month = {Fri Feb 10 00:00:00 EST 2017}
}
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