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arXiv · 2502.03026

Method for Determining the Parameters of a Ring-like Structure from the Visibility Function Shape

S. V. Chernov·M. A. Shchurov·I. I. Bulygin·A. G. Rudnitskiy
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Abstract

Black hole images obtained by very long baseline interferometry (VLBI) by the Event Horizon Telescope are a new tool for testing general relativity in super-strong gravitational fields. These images demonstrated a ring-like structure which can be explained as the black hole shadow image. To date, there are no reliable methods for determining the parameters of these ring-like structures, such as diameter, width, and asymmetry. In this paper, an algorithm for determining black hole image parameters is proposed using a Gaussian asymmetric ring as an example. Using the proposed method, the diameter and asymmetry parameters of the image of a supermassive black hole in the galaxy M87$^{*}$ were estimated based on observational data obtained by the Event Horizon Telescope group.

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S. V. Chernov, M. A. Shchurov, I. I. Bulygin, A. G. Rudnitskiy. 2025-02-05. Method for Determining the Parameters of a Ring-like Structure from the Visibility Function Shape. https://arxiv.org/abs/2502.03026

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