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Angular Power Spectrum of Gravitational-Wave Transient Sources as a Probe of the Large-Scale Structure
Yanyan Zheng1, Nikolaos Kouvatsos2, Jacob Golomb3,4
1Institute of Multi-messenger Astrophysics and Cosmology, Missouri University of Science and Technology, Physics Building, 1315 North Pine Street, Rolla, Missouri 65409, USA.
Physical Review Letters
|November 13, 2023
Summary
We developed a new simulation-based method to analyze gravitational-wave events. Applying it to binary black hole mergers, we found no evidence of unusual spatial distribution, supporting an isotropic sky.
Area of Science:
- Astrophysics
- Cosmology
- Gravitational-wave Astronomy
Background:
- Understanding the spatial distribution of gravitational-wave sources is crucial for cosmology.
- Previous analyses have explored source distributions, but new methods are needed for complex datasets.
Purpose of the Study:
- To introduce a novel simulation-based inference method for analyzing the angular power spectrum of gravitational-wave transients.
- To test the spatial distribution of binary black hole mergers observed during the third LIGO, Virgo, and KAGRA observing run.
Main Methods:
- Developed a new simulation-based inference technique.
- Computed the angular power spectrum of foreground gravitational-wave transient events.
- Applied the method to data from the LIGO, Virgo, and KAGRA third observing run.
Main Results:
- The study found no statistically significant evidence for anisotropy in the angular distribution of binary black hole mergers.
- The observed spatial distribution is consistent with isotropy.
Conclusions:
- The new method is effective for analyzing gravitational-wave source distributions.
- Current binary black hole merger data shows an isotropic sky distribution.
- Future applications include studying other source populations and their relation to the large-scale structure of the universe.
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