Determining Kerr black hole spin and inclination from a segment of the critical curve in black hole images

arXiv:2606.21921 · gr-qc, astro-ph.HE · Submitted 2026-06-20 · Read on arXiv

Kenta Hioki, Umpei Miyamoto, Tomohiro Harada

gr-qc, astro-ph.HE

Submitted: 2026-06-20

Comments: 34 pages, 8 figures, 2 tables

License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

Terminology

• Accuracy — 9× in this paper · explained in 1 episode
• Reconstruction Error — 3× in this paper · explained in 2 episodes
• Trace — 3× in this paper · explained in 2 episodes
• Accretion Flows — 2× in this paper · explained in 1 episode
• Degeneracy — 1× in this paper · explained in 3 episodes
• Gravitational Lensing — 1× in this paper · explained in 2 episodes
• Near-Horizon Extreme Kerr — 1× in this paper
• Principal Component Analysis (PCA) — 1× in this paper · explained in 4 episodes
• Robustness — 1× in this paper · explained in 5 episodes

Sources

• First M87 Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole
• First Sagittarius A* Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole in the Center of the Milky Way
• Hidden symmetries, null geodesics, and photon capture in the Sen black hole
• Measurement of the Kerr Spin Parameter by Observation of a Compact Object's Shadow
• Constraining the spin and the deformation parameters from the black hole shadow
• A coordinate-independent characterization of a black hole shadow
• Constraints on black-hole charges with the 2017 EHT observations of M87*
• Determining parameters of a spherical black hole with a thin accretion disk by observing its shadow
• Determining parameters of Kerr black holes at finite distance by shadow observation
• Determining parameters of Kerr-Newman black holes by shadow observation from finite distance and spatial infinity
• First M87 Event Horizon Telescope Results. IV. Imaging the Central Supermassive Black Hole
• Black Hole Shadows, Photon Rings, and Lensing Rings
• First M87 Event Horizon Telescope Results. V. Physical Origin of the Asymmetric Ring
• Advection-Dominated Accretion: A Self-Similar Solution
• Hot Accretion Flows Around Black Holes
• A public code for general relativistic, polarised radiative transfer around spinning black holes
• Universal Interferometric Signatures of a Black Hole's Photon Ring
• The Japanese Vision for the Black Hole Explorer Mission
• The Black Hole Explorer: Motivation and Vision
• The Black Hole Explorer: Photon Ring Science, Detection and Shape Measurement

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