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arXiv · 2603.18963

Observational Signatures of Rotating Ay\'{o}n-Beato-Garc\'{i}a Black Holes: Shadows, Accretion Disks and Images

Zhenglong Ban·Meng Chen·Rong-Jia Yang
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Abstract

We investigate the shadows, accretion disks, and observational images of rotating Ay\'on-Beato--Garc\'{\i}a (ABG) black holes with mass $M$, spin $a$, and nonlinear-electrodynamics (NLED) charge parameter $\zeta$, treating photons as neutral test particles on null geodesics of the background metric so as to obtain the purely geometric shadow. The shadow shrinks with increasing $\zeta$ and develops a ``D''-shaped morphology for near-extremal spin. The thermal disk properties follow from the Novikov--Thorne model with inner edge at the innermost stable circular orbit (ISCO), whereas the images use a separate, phenomenological optically thin emission model extending to the horizon. The image asymmetry and redshift maps depend strongly on $(a, \zeta)$ and the inclination. Comparing the geometric shadow diameters with Event Horizon Telescope observations of M87$^{*}$ and Sgr A$^{*}$ gives the indicative estimates $\zeta \lesssim 0.21\,M$ and $\zeta \lesssim 0.43\,M$, respectively; since $\zeta$ characterizes each black hole individually, these are quoted separately rather than combined, and the Kerr limit $\zeta = 0$ remains fully consistent with both.

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Zhenglong Ban, Meng Chen, Rong-Jia Yang. 2026-03-19. Observational Signatures of Rotating Ay\'{o}n-Beato-Garc\'{i}a Black Holes: Shadows, Accretion Disks and Images. https://arxiv.org/abs/2603.18963

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