6 papers
Exact Cancellation of Horizon Modes in Kerr Ringdown
Kei-ichiro Kubota, Yusuke Manita, Hayato Motohashi +1
Ringdown gravitational waves probe black hole spacetimes via quasinormal modes (QNMs). Recent studies have reported oscillatory features in QNM-filtered waveforms, and have led to…
Ringdown analysis of GW250114 with orthonormal modes
Motoki Suzuki, Kei-ichiro Kubota, Soichiro Morisaki +2
GW250114 is the loudest gravitational wave event to date observed by LIGO-Virgo-KAGRA Collaboration. Owing to its high signal-to-noise ratio (SNR), previous analyses based on quasi…
Inspiral-Transition-Plunge Gravitational Waveforms Beyond Kerr: A Kerr-Newman Case Study
Daiki Watarai, Kent Yagi, Shammi Tahura
Binary black hole mergers with asymmetric component masses are key targets for both third-generation ground-based and future space-based gravitational-wave (GW) detectors, offering…
Analyzing black-hole ringdowns with orthonormal modes
Soichiro Morisaki, Hayato Motohashi, Motoki Suzuki +1
The ringdown signal following a black hole (BH) merger can be modeled as a superposition of BH quasinormal modes (QNMs), offering a clean setup for testing gravitational theories.…
Ringdown of a postinnermost stable circular orbit of a rapidly spinning black hole: Mass ratio dependence of higher harmonic quasinormal mode excitation
Daiki Watarai
In a binary merger with a small mass ratio, as the secondary body approaches the innermost stable circular orbit (ISCO) of the primary black hole, the motion transitions from the a…
Slowly decaying ringdown of a rapidly spinning black hole II: Inferring the masses and spins of supermassive black holes with LISA
Daiki Watarai, Naritaka Oshita, Daichi Tsuna
Electromagnetic observations reveal that almost all galaxies have supermassive black holes (SMBHs) at their centers, but their properties, especially their spins, are not fully und…