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arXiv · 2304.06079

The Image of the M87 Black Hole Reconstructed with PRIMO

Lia Medeiros·Dimitrios Psaltis·Tod R. Lauer·Feryal Ozel
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Abstract

We present a new reconstruction of the Event Horizon Telescope (EHT) image of the M87 black hole from the 2017 data set. We use PRIMO, a novel dictionary-learning based algorithm that uses high-fidelity simulations of accreting black holes as a training set. By learning the correlations between the different regions of the space of interferometric data, this approach allows us to recover high-fidelity images even in the presence of sparse coverage and reach the nominal resolution of the EHT array. The black hole image comprises a thin bright ring with a diameter of $41.5\pm0.6\,\mu$as and a fractional width that is at least a factor of two smaller than previously reported. This improvement has important implications for measuring the mass of the central black hole in M87 based on the EHT images.

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Lia Medeiros, Dimitrios Psaltis, Tod R. Lauer, Feryal Ozel. 2023-04-12. The Image of the M87 Black Hole Reconstructed with PRIMO. https://doi.org/10.3847/2041-8213%2Facc32d

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