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Published on: February 12, 2013
Black Hole Mergers in the Universe.
The Astrophysical Journal
|December 10, 1999
Summary
Dynamical interactions in star clusters can form black hole binaries, leading to mergers. This predicts higher gravitational wave detection rates than neutron star mergers for observatories like LIGO.
Area of Science:
- Astrophysics
- Gravitational Wave Astronomy
Background:
- Black hole binary mergers are a key source of gravitational radiation.
- Current binary evolution models predict low merger rates, insufficient for significant observational interest.
Purpose of the Study:
- To investigate if dynamical interactions in dense stellar systems can increase black hole binary merger rates.
- To predict the merger rate and potential gravitational wave detection rates.
Main Methods:
- Modeling dynamical interactions in star clusters.
- Simulating the formation, hardening, and ejection of black hole binaries.
- Estimating merger timescales and gravitational wave event rates.
Main Results:
- Black holes in star clusters form binaries through dynamical relaxation and become tightly bound.
- These binaries are ejected and their mergers are driven by gravitational radiation.
- A predicted black hole merger rate of ~1.6x10^-7 yr^-1 Mpc^-3.
Conclusions:
- Dynamical formation of black hole binaries in star clusters significantly enhances merger rates.
- Gravitational wave observatories like LIGO are expected to detect these mergers at substantial rates.
- Detection rates are sensitive to cluster mass and early binary ejection.
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