Year: 2019
Type: article
Abstract: We analyze gravitational-wave data from the first LIGO detection of a binary black-hole merger (GW150914) in search of the ringdown of the remnant black hole. Using observations beginning at the peak of the signal, we find evidence of the fundamental quasinormal mode and at least one overtone, both associated with the dominant angular mode (ℓ=m=2), with 3.6σ confidence. A ringdown model including overtones allows us to measure the final mass and spin magnitude of the remnant exclusively from postinspiral data, obtaining an estimate in agreement with the values inferred from the full signal. The mass and spin values we measure from the ringdown agree with those obtained using solely the fundamental mode at a later time, but have smaller uncertainties. Agreement between the postinspiral measurements of mass and spin and those using the full waveform supports the hypothesis that the GW150914 merger produced a Kerr black hole, as predicted by general relativity, and provides a test of the no-hair theorem at the ∼10% level. An independent measurement of the frequency of the first overtone yields agreement with the no-hair hypothesis at the ∼20% level. As the detector sensitivity improves and the detected population of black-hole mergers grows, we can expect that using overtones will provide even stronger tests.
Source: Physical Review Letters
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Awards: G1036789809, The Operation and Maintenance of the Laser Interferometer Gravitational Wave Observatory (LIGO), G1575719080, G2032022763, G2273387815, G2904733527, G433322167, G4583451123, G58316358, G610330404, Gravitational Radiation and Relativistic Astrophysics, G6273510985, Collabortive Research: Petascale Simulations of Merging Black Holes and Neutron Stars, Maximizing Science Output of LIGO: Improved Detectors and Data Analysis, Research in Black-Hole Physics and Relativistic Astrophysics
OpenAlex ID: W2942867706
