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arXiv · 2008.02248

Binary black hole spectroscopy: a no-hair test of GW190814 and GW190412

Abstract

Gravitational waves provide a window to probe general relativity (GR) under extreme conditions. The recent observations of GW190412 and GW190814 are unique high-mass-ratio mergers that enable the observation of gravitational-wave harmonics beyond the dominant $(\ell, m) = (2, 2)$ mode. Using these events, we search for physics beyond GR by allowing the source parameters measured from the sub-dominant harmonics to deviate from that of the dominant mode. All results are consistent with GR. We constrain the chirp mass as measured by the $(\ell, m) = (3, 3)$ mode to be within $0_{-3}^{+5}\%$ of the dominant mode when we allow both the masses and spins of the sub-dominant modes to deviate. If we allow only the mass parameters to deviate, we constrain the chirp mass of the $(3, 3)$ mode to be within $\pm1\%$ of the expected value from GR.

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BibTeXRIS

Collin D. Capano, Alexander H. Nitz. 2020-08-05. Binary black hole spectroscopy: a no-hair test of GW190814 and GW190412. https://doi.org/10.1103/physrevd.102.124070

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