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Abstract Accurate modelling of black hole binaries is critical to achieve the science goals of gravitational-wave detectors. Modelling such configurations relies strongly on calibration to numerical-relativity (NR) simulations. Binaries on quasi-circular orbits have been widely explored in NR, however, coverage of the broader 9-dimensional parameter space, including orbital eccentricity, remains sparse. This article develops a new procedure to control orbital eccentricity of binary black hole simulations that enables choosing initial data parameters with precise control over eccentricity and mean anomaly of the subsequent evolution, as well as the coalescence time. We then calculate several sequences of NR simulations that nearly uniformly cover the 2-dimensional eccentricity--mean anomaly space for equal mass, non-spinning binary black holes. We demonstrate that, for fixed eccentricity, many quantities related to the merger dynamics of binary black holes show an oscillatory dependence on mean anomaly. The amplitude of these oscillations scales nearly linearly with the eccentricity of the system. We find that for the eccentricities explored in this work, the magnitude of deviations in various quantities such as the merger amplitude and peak luminosity can approach $$\sim5\%$$ of their quasi-circular value. We use our findings to explain eccentric phenomena reported in other studies. We also show that methods for estimating the remnant mass employed in the effective-one-body approach exhibit similar deviations, roughly matching the amplitude of the oscillations we find in NR simulations. This work is an important step towards a complete description of eccentric binary black hole mergers, and demonstrates the importance of considering the entire 2-dimensional parameter subspace related to eccentricity.
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Close encounter of three black holes revisited
We study the evolution of close triple black hole system with full numerical relativity techniques. We consider an equal mass non spinning hierarchical system with an inner binary ten orbits away from merger and study the effects of the third outer black hole on the binary’s merger time and its eccentricity evolution. We find a generic time delay and an increase in the number of orbits to merger of the binary, that can be modeled versus the distance D to the third black hole as ∼1=D^2.5 . On the other hand, we find that the orientation of the third black hole orbit has little effect on the binary’s merger time when considering a fiducial initial distance of D = 30M to the binary (with initial orbital separation d = 8M). In those scenarios the evolution of the inner binary eccentricity presents a steady decay, roughly as expected, but in addition shows a modulation with the time
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- Award ID(s):
- 2207920
- PAR ID:
- 10532426
- Publisher / Repository:
- American Physical Society
- Date Published:
- Journal Name:
- Physical Review D
- Volume:
- 108
- Issue:
- 6
- ISSN:
- 2470-0010
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1103/PhysRevD.108.064045
