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arXiv · 2112.05829

Self-lensing flares from black hole binaries II: observing black hole shadows via light-curve tomography

Jordy Davelaar·Zoltán Haiman
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Abstract

Supermassive black hole (BH) binaries are thought to produce self-lensing flares (SLF) when the two BHs are aligned with the line-of-sight. If the binary orbit is observed nearly edge-on, we find a distinct feature in the light curve imprinted by the BH shadow from the lensed BH. We study this feature by ray-tracing in a binary model and predict that 1\% of the current binary candidates could show this feature. Our BH tomography method proposed here could make it possible to extract BH shadows that are spatially unresolvable by high-resolution VLBI.

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Jordy Davelaar, Zoltán Haiman. 2021-12-10. Self-lensing flares from black hole binaries II: observing black hole shadows via light-curve tomography. https://doi.org/10.1103/physrevlett.128.191101

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