2020/10/31 by Ollie Burke, J. R. Gair, Jonathan R. Gair +3
Physics and Astronomy · #Adiabatic process #Astrophysical Phenomena and Observations #Astrophysics #Black Holes and Theoretical Physics #Black hole (networking) #Condensed matter physics #Context (archaeology) #Geodesic #Geometry #Gravitational wave #Physics #Pulsars and Gravitational Waves Research #Quantum mechanics #Spin (aerodynamics) #Spins #gr-qc #hep-th
paper · pdf · doi:10.1103/physrevd.102.124054
published as Phys. Rev. D 102, 124054 (2020) · 31 pages, 18 figures, 1 table. Accepted for publication in Phys. Rev. D
arxiv created 2020/12/06 · openalex publication_date 2020/12/22 · arxiv updated 2021/01/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We describe a model that generates first order adiabatic extreme mass ratio inspiral waveforms for quasi-circular equatorial inspirals of compact objects into rapidly rotating (near-extremal) black holes. Using our model, we show that LISA could measure the spin parameter of near-extremal black holes (for a\ensuremath\gtrsim0.9999) with extraordinary precision, \ensuremath∼3\ensuremath-4 orders of magnitude better than for moderate spins, a\ensuremath∼0.9. Such spin measurements would be one of the tightest measurements of an astrophysical parameter within a gravitational wave context. Our results are primarily based off a Fisher matrix analysis, but are verified using both frequentist and Bayesian techniques. We present analytical arguments that explain these high spin precision measurements. The high precision arises from the spin dependence of the radial inspiral evolution, which is dominated by geodesic properties of the secondary orbit, rather than radiation reaction. High precision measurements are only possible if we observe the exponential damping of the signal that is characteristic of the near-horizon regime of near-extremal inspirals. Our results demonstrate that, if such black holes exist, LISA would be able to successfully identify rapidly rotating black holes up to a=1\ensuremath-10^\ensuremath-9, far past the Thorne limit of a=0.998.