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This content will become publicly available on May 1, 2023

Title: Selective Dynamical Imaging of Interferometric Data
Abstract Recent developments in very long baseline interferometry (VLBI) have made it possible for the Event Horizon Telescope (EHT) to resolve the innermost accretion flows of the largest supermassive black holes on the sky. The sparse nature of the EHT’s ( u , v )-coverage presents a challenge when attempting to resolve highly time-variable sources. We demonstrate that the changing ( u , v )-coverage of the EHT can contain regions of time over the course of a single observation that facilitate dynamical imaging. These optimal time regions typically have projected baseline distributions that are approximately angularly isotropic and radially homogeneous. We derive a metric of coverage quality based on baseline isotropy and density that is capable of ranking array configurations by their ability to produce accurate dynamical reconstructions. We compare this metric to existing metrics in the literature and investigate their utility by performing dynamical reconstructions on synthetic data from simulated EHT observations of sources with simple orbital variability. We then use these results to make recommendations for imaging the 2017 EHT Sgr A* data set.
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Award ID(s):
1935980 2034306 1743747
Publication Date:
NSF-PAR ID:
10343420
Journal Name:
The Astrophysical Journal Letters
Volume:
930
Issue:
2
Page Range or eLocation-ID:
L18
ISSN:
2041-8205
Sponsoring Org:
National Science Foundation
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