Selective Dynamical Imaging of Interferometric Data
Authors: Farah Joseph , Galison Peter , Akiyama Kazunori , Bouman Katherine L. , Bower Geoffrey C. , Chael Andrew , Fuentes Antonio , Gómez José L. , Honma Mareki , Johnson Michael D. , Kofuji Yutaro , Marrone Daniel P. , Moriyama Kotaro , Narayan Ramesh , Pesce Dominic W. , Tiede Paul , Wielgus Maciek , Zhao Guang-Yao ,   The Event Horizon Telescope Collaboration, Alberdi Antxon , Alef Walter , Algaba Juan Carlos , Anantua Richard , Asada Keiichi , Azulay Rebecca , Baczko Anne-Kathrin , Ball David , Baloković Mislav , Barrett John , Benson Bradford A. , Bintley Dan , Blackburn Lindy , Blundell Raymond , Boland Wilfred , Boyce Hope , Bremer Michael , Brinkerink Christiaan D. , Brissenden Roger , Britzen Silke , Broderick Avery E. , Broguiere Dominique , Bronzwaer Thomas , Bustamente Sandra , Byun Do-Young , Carlstrom John E. , Chan Chi-kwan , Chatterjee Koushik , Chatterjee Shami , Chen Ming-Tang , Chen 陈 Yongjun 永 军 , Cho Ilje , Christian Pierre , Conway John E. , Cordes James M. , Crawford Thomas M. , Crew Geoffrey B. , Cruz-Osorio Alejandro , Cui Yuzhu , Davelaar Jordy , Laurentis Mariafelicia De , Deane Roger , Dempsey Jessica , Desvignes Gregory , Doeleman Sheperd S. , Eatough Ralph P. , Falcke Heino , Fish Vincent L. , Fomalont Ed , Ford H. Alyson , Fraga-Encinas Raquel , Friberg Per , Fromm Christian M. , Gammie Charles F. , Garc’a Roberto , Gentaz Olivier , Goddi Ciriaco , Gold Roman , Gómez-Ruiz Arturo I. , Gu 顾 Minfeng 敏 峰 , Gurwell Mark , Hada Kazuhiro , Haggard Daryl , Hecht Michael H. , Hesper Ronald , Ho 何 Luis C. 子 山 , Ho Paul , Huang Chih-Wei L. , Huang 黄 Lei 磊 , Hughes David H. , Ikeda Shiro , Inoue Makoto , Issaoun Sara , James David J. , Jannuzi Buell T. , Janssen Michael , Jeter Britton , Jiang 江 Wu 悟 , Jimenez-Rosales Alejandra , Jorstad Svetlana , Jung Taehyun , Karami Mansour , Karuppusamy Ramesh , Kawashima Tomohisa , Keating Garrett K. , Kettenis Mark , Kim Dong-Jin , Kim Jae-Young , Kim Jongsoo , Kim Junhan , Kino Motoki , Koay Jun Yi , Koch Patrick M. , Koyama Shoko , Kramer Carsten , Kramer Michael , Krichbaum Thomas P. , Kuo Cheng-Yu , Lauer Tod R. , Lee Sang-Sung , Levis Aviad , Li Yan-Rong , Li 李 Zhiyuan 志 远 , Lico Rocco , Lindahl Greg , Lindqvist Michael , Liu 刘 Jun 俊 , Liu Kuo , Liuzzo Elisabetta , Lo Wen-Ping , Lobanov Andrei P. , Loinard Laurent , Lonsdale Colin , Lu 路 Ru-Sen 如 森 , MacDonald Nicholas R. , Mao 毛 Jirong 基 荣 , Marchili Nicola , Markoff Sera , Marscher Alan P. , Martí-Vidal Iván , Matsushita Satoki , Matthews Lynn D. , Medeiros Lia , Menten Karl M. , Mizuno Izumi , Mizuno Yosuke , Moran James M. , Moscibrodzka Monika , Müller Cornelia , Mejas Alejandro Mus , Musoke Gibwa , Nagai Hiroshi , Nagar Neil M. , Nakamura Masanori , Narayanan Gopal , Natarajan Iniyan , Nathanail Antonios , Neilsen Joey , Neri Roberto , Ni Chunchong , Noutsos Aristeidis , Nowak Michael A. , Okino Hiroki , Olivares Héctor , Ortiz-León Gisela N. , Oyama Tomoaki , zel Feryal , Palumbo Daniel C. M. , Park Jongho , Patel Nimesh , Pen Ue-Li , Piétu Vincent , Plambeck Richard , PopStefanija Aleksandar , Porth Oliver , Pötzl Felix M. , Prather Ben , Preciado-López Jorge A. , Psaltis Dimitrios , Pu Hung-Yi , Ramakrishnan Venkatessh , Rao Ramprasad , Rawlings Mark G. , Raymond Alexander W. , Rezzolla Luciano , Ripperda Bart , Roelofs Freek , Rogers Alan , Ros Eduardo , Rose Mel , Roshanineshat Arash , Rottmann Helge , Roy Alan L. , Ruszczyk Chet , Rygl Kazi L. J. , Sánchez Salvador , Sánchez-Arguelles David , Sasada Mahito , Savolainen Tuomas , Schloerb F. Peter , Schuster Karl-Friedrich , Shao Lijing , Shen 沈 Zhiqiang 志 强 , Small Des , Sohn Bong Won , SooHoo Jason , Sun 孙 He 赫 , Tazaki Fumie , Tetarenko Alexandra J. , Tilanus Remo P. J. , Titus Michael , Toma Kenji , Torne Pablo , Traianou Efthalia , Trent Tyler , Trippe Sascha , Bemmel Ilse van , van Langevelde Huib Jan , van Rossum Daniel R. , Wagner Jan , Ward-Thompson Derek , Wardle John , Weintroub Jonathan , Wex Norbert , Wharton Robert , Wiik Kaj , Wong George N. , Wu Qingwen , Yoon Doosoo , Young André , Young Ken , Younsi Ziri , Yuan 袁 Feng 峰 , Yuan 袁 Ye-Fei 业 飞 , Zensus J. Anton , Zhao Shan-Shan 
Published: May 2022

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.