Alexander Graham Bell Canada Graduate Scholarships-Doc-
toral Program); the National Youth Thousand Talents Program
of China; the National Research Foundation of Korea (the
Global PhD Fellowship Grant: grants NRF-
2015H1A2A1033752, the Korea Research Fellowship Pro-
gram: NRF-2015H1D3A1066561, Brain Pool Program:
2019H1D3A1A01102564, Basic Research Support Grant
2019R1F1A1059721,
2021R1A6A3A01086420,
2022R1C1C1005255); Netherlands Research School for
Astronomy (NOVA) Virtual Institute of Accretion (VIA)
postdoctoral fellowships; Onsala Space Observatory (OSO)
national infrastructure, for the provisioning of its facilities/
observational support (OSO receives funding through the
Swedish Research Council under grant 2017-00648); the
Perimeter Institute for Theoretical Physics (research at
Perimeter Institute is supported by the Government of Canada
through the Department of Innovation, Science and Economic
Development and by the Province of Ontario through the
Ministry of Research, Innovation and Science); the Spanish
Ministerio de Ciencia e Innovación (grants PGC2018-098915-
B-C21, AYA2016-80889-P, PID2019-108995GB-C21,
PID2020-117404GB-C21); the University of Pretoria for
financial aid in the provision of the new Cluster Server nodes
and SuperMicro (USA) for a SEEDING GRANT approved
towards these nodes in 2020; the Shanghai Pilot Program for
Basic Research, Chinese Academy of Science, Shanghai
Branch (JCYJ-SHFY-2021-013); the State Agency for
Research of the Spanish MCIU through the “Center of
Excellence Severo Ochoa” award for the Instituto de Astro-
física de Andalucía (SEV-2017-0709); the Spinoza Prize SPI
78-409; the South African Research Chairs Initiative, through
the South African Radio Astronomy Observatory (SARAO,
grant ID 77948), which is a facility of the National Research
Foundation (NRF), an agency of the Department of Science
and Innovation (DSI) of South Africa; the Toray Science
Foundation; Swedish Research Council (VR); the US Depart-
ment of Energy (USDOE) through the Los Alamos National
Laboratory (operated by Triad National Security, LLC, for the
National Nuclear Security Administration of the USDOE
(Contract 89233218CNA000001); and the YCAA Prize
Postdoctoral Fellowship.

We thank the staff at the participating observatories,
correlation centers, and institutions for their enthusiastic
support. This paper makes use of the following ALMA data:
ADS/JAO.ALMA#2016.1.01154.V. ALMA is a partnership
of the European Southern Observatory (ESO; Europe,
representing its member states), NSF, and National Institutes
of Natural Sciences of Japan, together with National Research
Council (Canada), Ministry of Science and Technology
(MOST; Taiwan), Academia Sinica Institute of Astronomy
and Astrophysics (ASIAA; Taiwan), and Korea Astronomy and
Space Science Institute (KASI; Republic of Korea), in
cooperation with the Republic of Chile. The Joint ALMA
Observatory is operated by ESO, Associated Universities, Inc.
(AUI)/NRAO, and the National Astronomical Observatory of
Japan (NAOJ). The NRAO is a facility of the NSF operated
under cooperative agreement by AUI. This research used
resources of the Oak Ridge Leadership Computing Facility at
the Oak Ridge National Laboratory, which is supported by the
Office of Science of the U.S. Department of Energy under
Contract No. DE-AC05-00OR22725. We also thank the
Center for Computational Astrophysics, National Astronomical

Observatory of Japan. The computing cluster of Shanghai
VLBI correlator supported by the Special Fund for Astronomy
from the Ministry of Finance in China is acknowledged.

APEX is a collaboration between the Max-Planck-Institut für Radioastronomie (Germany), ESO, and the Onsala Space Observatory (Sweden). The SMA is a joint project between the SAO and ASIAA and is funded by the Smithsonian Institution and the Academia Sinica. The JCMT is operated by the East Asian Observatory on behalf of the NAOJ, ASIAA, and KASI, as well as the Ministry of Finance of China, Chinese Academy of Sciences, and the National Key Research and Development Program (No. 2017YFA0402700) of China and Natural Science Foundation of China grant 11873028. Additional funding support for the JCMT is provided by the Science and Technologies Facility Council (UK) and participating universities in the UK and Canada. The LMT is a project operated by the Instituto Nacional de Astrófisica, Óptica, y Electrónica (Mexico) and the University of Massachusetts at Amherst (USA). The IRAM 30-m telescope on Pico Veleta, Spain is operated by IRAM and supported by CNRS (Centre National de la Recherche Scientifique, France), MPG (Max-Planck-Gesellschaft, Germany) and IGN (Instituto Geográfico Nacional, Spain). The SMT is operated by the Arizona Radio Observatory, a part of the Steward Observatory of the University of Arizona, with financial support of operations from the State of Arizona and financial support for instrumentation development from the NSF. Support for SPT participation in the EHT is provided by the National Science Foundation through award OPP-1852617 to the University of Chicago. Partial support is also provided by the Kavli Institute of Cosmological Physics at the University of Chicago. The SPT hydrogen maser was provided on loan from the GLT, courtesy of ASIAA.

This work used the Extreme Science and Engineering
Discovery Environment (XSEDE), supported by NSF grant
ACI-1548562, and CyVerse, supported by NSF grants DBI-
0735191, DBI-1265383, and DBI-1743442. XSEDE Stam-
pede2 resource at TACC was allocated through TG-
AST170024 and TG-AST080026N. XSEDE JetStream
resource at PTI and TACC was allocated through
AST170028. This research is part of the Frontera computing
project at the Texas Advanced Computing Center through the
Frontera Large-Scale Community Partnerships allocation
AST20023. Frontera is made possible by National Science
Foundation award OAC-1818253. This research was carried
out using resources provided by the Open Science Grid, which
is supported by the National Science Foundation and the U.S.
Department of Energy Office of Science.

Additional work used ABACUS2.0, which is part of the
eScience center at Southern Denmark University. Simulations
were also performed on the SuperMUC cluster at the LRZ in
Garching, on the LOEWE cluster in CSC in Frankfurt, on the
HazelHen cluster at the HLRS in Stuttgart, and on the Pi2.0 and
Siyuan Mark-I at Shanghai Jiao Tong University. The computer
resources of the Finnish IT Center for Science (CSC) and the
Finnish Computing Competence Infrastructure (FCCI) project
are acknowledged. This research was enabled in part by support
provided by Compute Ontario (http://computeontario.ca),
Calcul Quebec (http://www.calculquebec.ca) and Compute
Canada (http://www.computecanada.ca).

The EHTC has received generous donations of FPGA chips
from Xilinx Inc., under the Xilinx University Program. The
EHTC has benefited from technology shared under open-
source license by the Collaboration for Astronomy Signal
Processing and Electronics Research (CASPER). The EHT
project is grateful to T4Science and Microsemi for their
assistance with Hydrogen Masers. This research has made use
of NASA's Astrophysics Data System. We gratefully acknowl-
edge the support provided by the extended staff of the ALMA,
both from the inception of the ALMA Phasing Project through
the observational campaigns of 2017 and 2018. We would like
to thank A. Deller and W. Brisken for EHT-specific support
with the use of DiFX. We thank Martin Shepherd for the
addition of extra features in the Difmap software that were used
for the CLEAN imaging results presented in this paper. We
acknowledge the significance that Maunakea, where the SMA
and JCMT EHT stations are located, has for the indigenous
Hawaiian people.

Facility: EHT

ORCID iDs

Kazunori Akiyama https://orcid.org/0000-0002-9475-4254

Antxon Alberdi https://orcid.org/0000-0002-9371-1033

Juan Carlos Algaba https://orcid.org/0000-0001-6993-1696

Richard Anantua https://orcid.org/0000-0003-3457-7660

Keiichi Asada https://orcid.org/0000-0001-6988-8763

Rebecca Azulay https://orcid.org/0000-0002-2200-5393

Uwe Bach https://orcid.org/0000-0002-7722-8412

Anne-Kathrin Baczko https://orcid.org/0000-0003-3090-3975

Mislav Baloković https://orcid.org/0000-0003-0476-6647

John Barrett https://orcid.org/0000-0002-9290-0764

Michi Bauböck https://orcid.org/0000-0002-5518-2812

Bradford A. Benson https://orcid.org/0000-0002-5108-6823

Lindy Blackburn https://orcid.org/0000-0002-9030-642X

Raymond Blundell https://orcid.org/0000-0002-5929-5857

Katherine L. Bouman https://orcid.org/0000-0003-0077-4367

Geoffrey C. Bower https://orcid.org/0000-0003-4056-9982

Hope Boyce https://orcid.org/0000-0002-6530-5783

Christiaan D. Brinkerink https://orcid.org/0000-0002-2322-0749

Roger Brissenden https://orcid.org/0000-0002-2556-0894

Silke Britzen https://orcid.org/0000-0001-9240-6734

Avery E. Broderick https://orcid.org/0000-0002-3351-760X

Dominique Broguiere https://orcid.org/0000-0001-9151-6683

Thomas Bronzwaer https://orcid.org/0000-0003-1151-3971

Sandra Bustamante https://orcid.org/0000-0001-6169-1894

Do-Young Byun https://orcid.org/0000-0003-1157-4109

John E. Carlstrom https://orcid.org/0000-0002-2044-7665

Chiara Ceccobello https://orcid.org/0000-0002-4767-9925

Andrew Chael https://orcid.org/0000-0003-2966-6220

Chi-kwan Chan https://orcid.org/0000-0001-6337-6126

Koushik Chatterjee https://orcid.org/0000-0002-2825-3590

Shami Chatterjee https://orcid.org/0000-0002-2878-1502

Ming-Tang Chen https://orcid.org/0000-0001-6573-3318

Yongjun Chen (陈永军) https://orcid.org/0000-0001-5650-6770

Xiaopeng Cheng https://orcid.org/0000-0003-4407-9868

Ilje Cho https://orcid.org/0000-0001-6083-7521

Pierre Christian https://orcid.org/0000-0001-6820-9941

Nicholas S. Conroy https://orcid.org/0000-0003-2886-2377

John E. Conway https://orcid.org/0000-0003-2448-9181

James M. Cordes https://orcid.org/0000-0002-4049-1882

Thomas M. Crawford https://orcid.org/0000-0001-9000-5013

Geoffrey B. Crew https://orcid.org/0000-0002-2079-3189

Alejandro Cruz-Osorio https://orcid.org/0000-0002-3945-6342

Yuzhu Cui (崔玉竹) https://orcid.org/0000-0001-6311-4345

Jordy Davelaar https://orcid.org/0000-0002-2685-2434

Mariafelicia De Laurentis https://orcid.org/0000-0002-9945-682X

Roger Deane https://orcid.org/0000-0003-1027-5043

Jessica Dempsey https://orcid.org/0000-0003-1269-9667

Gregory Desvignes https://orcid.org/0000-0003-3922-4055

Jason Dexter https://orcid.org/0000-0003-3903-0373

Vedant Dhruv https://orcid.org/0000-0001-6765-877X

Sheperd S. Doeleman https://orcid.org/0000-0002-9031-0904

Sean Dougal https://orcid.org/0000-0002-3769-1314

Sergio A. Dzib https://orcid.org/0000-0001-6010-6200

Ralph P. Eatough https://orcid.org/0000-0001-6196-4135

Razieh Emami https://orcid.org/0000-0002-2791-5011

Heino Falcke https://orcid.org/0000-0002-2526-6724

Joseph Farah https://orcid.org/0000-0003-4914-5625

Vincent L. Fish https://orcid.org/0000-0002-7128-9345

Ed Fomalont https://orcid.org/0000-0002-9036-2747

H. Alyson Ford https://orcid.org/0000-0002-9797-0972

Raquel Fraga-Encinas https://orcid.org/0000-0002-5222-1361

Per Friberg https://orcid.org/0000-0002-8010-8454

Christian M. Fromm https://orcid.org/0000-0002-1827-1656

Antonio Fuentes https://orcid.org/0000-0002-8773-4933

Peter Galison https://orcid.org/0000-0002-6429-3872

Charles F. Gammie https://orcid.org/0000-0001-7451-8935

Roberto García https://orcid.org/0000-0002-6584-7443

Olivier Gentaz https://orcid.org/0000-0002-0115-4605

Boris Georgiev https://orcid.org/0000-0002-3586-6424

Ciriaco Goddi https://orcid.org/0000-0002-2542-7743

Roman Gold https://orcid.org/0000-0003-2492-1966

Arturo I. Gómez-Ruiz https://orcid.org/0000-0001-9395-1670

José L. Gómez https://orcid.org/0000-0003-4190-7613

Minfeng Gu (顾敏峰) https://orcid.org/0000-0002-4455-6946

Mark Gurwell https://orcid.org/0000-0003-0685-3621

Kazuhiro Hada https://orcid.org/0000-0001-6906-772X

Daryl Haggard https://orcid.org/0000-0001-6803-2138

Michael H. Hecht https://orcid.org/0000-0002-4114-4583

Ronald Hesper https://orcid.org/0000-0003-1918-6098

Dirk Heumann https://orcid.org/0000-0002-7671-0047

Luis C. Ho

(何子山) https://orcid.org/0000-0001-6947-5846

Paul Ho https://orcid.org/0000-0002-3412-4306

Mareki Honma https://orcid.org/0000-0003-4058-9000

Chih-Wei L. Huang https://orcid.org/0000-0001-5641-3953

Lei Huang (黄磊) https://orcid.org/0000-0002-1923-227X
Shiro Ikeda https://orcid.org/0000-0002-2462-1448

C. M. Violette Impellizzeri https://orcid.org/0000-0002-3443-2472

Makoto Inoue https://orcid.org/0000-0001-5037-3989

Sara Issaoun https://orcid.org/0000-0002-5297-921X

David J. James https://orcid.org/0000-0001-5160-4486

Buell T. Jannuzi https://orcid.org/0000-0002-1578-6582

Michael Janssen https://orcid.org/0000-0001-8685-6544

Britton Jeter https://orcid.org/0000-0003-2847-1712

Wu Jiang (江悟) https://orcid.org/0000-0001-7369-3539

Alejandra Jiménez-Rosales https://orcid.org/0000-0002-2662-3754

Michael D. Johnson https://orcid.org/0000-0002-4120-3029

Svetlana Jorstad https://orcid.org/0000-0001-6158-1708

Abhishek V. Joshi https://orcid.org/0000-0002-2514-5965

Taehyun Jung https://orcid.org/0000-0001-7003-8643

Mansour Karami https://orcid.org/0000-0001-7387-9333

Ramesh Karuppusamy https://orcid.org/0000-0002-5307-2919

Tomohisa Kawashima https://orcid.org/0000-0001-8527-0496

Garrett K. Keating https://orcid.org/0000-0002-3490-146X

Mark Kettenis https://orcid.org/0000-0002-6156-5617

Dong-Jin Kim https://orcid.org/0000-0002-7038-2118

Jae-Young Kim https://orcid.org/0000-0001-8229-7183

Jongsoo Kim https://orcid.org/0000-0002-1229-0426

Junhan Kim https://orcid.org/0000-0002-4274-9373

Motoki Kino https://orcid.org/0000-0002-2709-7338

Jun Yi Koay https://orcid.org/0000-0002-7029-6658

Prashant Kocherlakota https://orcid.org/0000-0001-7386-7439

Patrick M. Koch https://orcid.org/0000-0003-2777-5861

Shoko Koyama https://orcid.org/0000-0002-3723-3372

Carsten Kramer https://orcid.org/0000-0002-4908-4925

Michael Kramer https://orcid.org/0000-0002-4175-2271

Thomas P. Krichbaum https://orcid.org/0000-0002-4892-9586

Cheng-Yu Kuo https://orcid.org/0000-0001-6211-5581

Noemi La Bella https://orcid.org/0000-0002-8116-9427

Tod R. Lauer https://orcid.org/0000-0003-3234-7247

Daeyoung Lee https://orcid.org/0000-0002-3350-5588

Sang-Sung Lee https://orcid.org/0000-0002-6269-594X

Po Kin Leung https://orcid.org/0000-0002-8802-8256

Aviad Levis https://orcid.org/0000-0001-7307-632X

Zhiyuan Li

(李志远) https://orcid.org/0000-0003-0355-6437

Rocco Lico https://orcid.org/0000-0001-7361-2460

Greg Lindahl https://orcid.org/0000-0002-6100-4772

Michael Lindqvist https://orcid.org/0000-0002-3669-0715

Mikhail Lisakov https://orcid.org/0000-0001-6088-3819

Jun Liu (刘俊) https://orcid.org/0000-0002-7615-7499

Kuo Liu https://orcid.org/0000-0002-2953-7376

Elisabetta Liuzzo https://orcid.org/0000-0003-0995-5201

Wen-Ping Lo https://orcid.org/0000-0003-1869-2503

Andrei P. Lobanov https://orcid.org/0000-0003-1622-1484

Laurent Loinard https://orcid.org/0000-0002-5635-3345

Colin J. Lonsdale https://orcid.org/0000-0003-4062-4654

Ru-Sen Lu

(路如森) https://orcid.org/0000-0002-7692-7967

Jirong Mao

(毛基荣) https://orcid.org/0000-0002-7077-7195

Nicola Marchili https://orcid.org/0000-0002-5523-7588

Sera Markoff https://orcid.org/0000-0001-9564-0876

Daniel P. Marrone https://orcid.org/0000-0002-2367-1080

Alan P. Marscher https://orcid.org/0000-0001-7396-3332

Iván Martí-Vidal https://orcid.org/0000-0003-3708-9611

Satoki Matsushita https://orcid.org/0000-0002-2127-7880

Lynn D. Matthews https://orcid.org/0000-0002-3728-8082

Lia Medeiros https://orcid.org/0000-0003-2342-6728

Karl M. Menten https://orcid.org/0000-0001-6459-0669

Daniel Michalik https://orcid.org/0000-0002-7618-6556

Izumi Mizuno https://orcid.org/0000-0002-7210-6264

Yosuke Mizuno https://orcid.org/0000-0002-8131-6730

James M. Moran https://orcid.org/0000-0002-3882-4414

Kotaro Moriyama https://orcid.org/0000-0003-1364-3761

Monika Moscibrodzka https://orcid.org/0000-0002-4661-6332

Cornelia Müller https://orcid.org/0000-0002-2739-2994

Alejandro Mus https://orcid.org/0000-0003-0329-6874

Gibwa Musoke https://orcid.org/0000-0003-1984-189X

Ioannis Myserlis https://orcid.org/0000-0003-3025-9497

Andrew Nadolski https://orcid.org/0000-0001-9479-9957

Hiroshi Nagai https://orcid.org/0000-0003-0292-3645

Neil M. Nagar https://orcid.org/0000-0001-6920-662X

Masanori Nakamura https://orcid.org/0000-0001-6081-2420

Ramesh Narayan https://orcid.org/0000-0002-1919-2730

Gopal Narayanan https://orcid.org/0000-0002-4723-6569

Iniyan Natarajan https://orcid.org/0000-0001-8242-4373

Joey Neilsen https://orcid.org/0000-0002-8247-786X

Roberto Neri https://orcid.org/0000-0002-7176-4046

Chunchong Ni https://orcid.org/0000-0003-1361-5699

Aristeidis Noutsos https://orcid.org/0000-0002-4151-3860

Michael A. Nowak https://orcid.org/0000-0001-6923-1315

Junghwan Oh https://orcid.org/0000-0002-4991-9638

Hiroki Okino https://orcid.org/0000-0003-3779-2016

Héctor Olivares https://orcid.org/0000-0001-6833-7580

Gisela N. Ortiz-León https://orcid.org/0000-0002-2863-676X

Tomoaki Oyama https://orcid.org/0000-0003-4046-2923

Feryal Özel https://orcid.org/0000-0003-4413-1523

Daniel C. M. Palumbo https://orcid.org/0000-0002-7179-3816

Georgios Filippos Paraschos https://orcid.org/0000-0001-6757-3098

Jongho Park https://orcid.org/0000-0001-6558-9053

Harriet Parsons https://orcid.org/0000-0002-6327-3423

Nimesh Patel https://orcid.org/0000-0002-6021-9421

Ue-Li Pen https://orcid.org/0000-0003-2155-9578

Dominic W. Pesce https://orcid.org/0000-0002-5278-9221

Richard Plambeck https://orcid.org/0000-0001-6765-9609

Oliver Porth https://orcid.org/0000-0002-4584-2557

Felix M. Pötzl https://orcid.org/0000-0002-6579-8311

Ben Prather https://orcid.org/0000-0002-0393-7734

Jorge A. Preciado-López https://orcid.org/0000-0002-4146-0113

Dimitrios Psaltis https://orcid.org/0000-0003-1035-3240

Hung-Yi Pu https://orcid.org/0000-0001-9270-8812

Venkatessh Ramakrishnan https://orcid.org/0000-0002-9248-086X

Ramprasad Rao https://orcid.org/0000-0002-1407-7944

Mark G. Rawlings https://orcid.org/0000-0002-6529-202X

Alexander W. Raymond https://orcid.org/0000-0002-5779-4767
Luciano Rezzolla https://orcid.org/0000-0002-1330-7103

Angelo Ricarte https://orcid.org/0000-0001-5287-0452

Bart Ripperda https://orcid.org/0000-0002-7301-3908

Freek Roelofs https://orcid.org/0000-0001-5461-3687

Alan Rogers https://orcid.org/0000-0003-1941-7458

Eduardo Ros https://orcid.org/0000-0001-9503-4892

Cristina Romero-Cañizales https://orcid.org/0000-0001-6301-9073

Arash Roshanineshat https://orcid.org/0000-0002-8280-9238

Alan L. Roy https://orcid.org/0000-0002-1931-0135

Ignacio Ruiz https://orcid.org/0000-0002-0965-5463

Chet Ruszczyk https://orcid.org/0000-0001-7278-9707

Kazi L. J. Rygl https://orcid.org/0000-0003-4146-9043

Salvador Sánchez https://orcid.org/0000-0002-8042-5951

David Sánchez-Argüelles https://orcid.org/0000-0002-7344-9920

Miguel Sánchez-Portal https://orcid.org/0000-0003-0981-9664

Mahito Sasada https://orcid.org/0000-0001-5946-9960

Kaushik Satapathy https://orcid.org/0000-0003-0433-3585

Tuomas Savolainen https://orcid.org/0000-0001-6214-1085

Jonathan Schonfeld https://orcid.org/0000-0002-8909-2401

Karl-Friedrich Schuster https://orcid.org/0000-0003-2890-9454

Lijing Shao https://orcid.org/0000-0002-1334-8853

Zhiqiang Shen

(沈志强) https://orcid.org/0000-0003-3540-8746

Des Small https://orcid.org/0000-0003-3723-5404

Bong Won Sohn https://orcid.org/0000-0002-4148-8378

Jason SooHoo https://orcid.org/0000-0003-1938-0720

Kamal Souccar https://orcid.org/0000-0001-7915-5272

He Sun (孙赫) https://orcid.org/0000-0003-1526-6787

Fumie Tazaki https://orcid.org/0000-0003-0236-0600

Alexandra J. Tetarenko https://orcid.org/0000-0003-3906-4354

Paul Tiede https://orcid.org/0000-0003-3826-5648

Remo P. J. Tilanus https://orcid.org/0000-0002-6514-553X

Michael Titus https://orcid.org/0000-0001-9001-3275

Pablo Torne https://orcid.org/0000-0001-8700-6058

Efthalia Traianou https://orcid.org/0000-0002-1209-6500

Sascha Trippe https://orcid.org/0000-0003-0465-1559

Matthew Turk https://orcid.org/0000-0002-5294-0198

Ilse van Bemmel https://orcid.org/0000-0001-5473-2950

Huib Jan van Langevelde https://orcid.org/0000-0002-0230-5946

Daniel R. van Rossum https://orcid.org/0000-0001-7772-6131

Jesse Vos https://orcid.org/0000-0003-3349-7394

Jan Wagner https://orcid.org/0000-0003-1105-6109

Derek Ward-Thompson https://orcid.org/0000-0003-1140-2761

John Wardle https://orcid.org/0000-0002-8960-2942

Jonathan Weintroub https://orcid.org/0000-0002-4603-5204

Norbert Wex https://orcid.org/0000-0003-4058-2837

Robert Wharton https://orcid.org/0000-0002-7416-5209

Maciek Wielgus https://orcid.org/0000-0002-8635-4242

Kaj Wiik https://orcid.org/0000-0002-0862-3398

Gunther Witzel https://orcid.org/0000-0003-2618-797X

Michael F. Wondrak https://orcid.org/0000-0002-6894-1072

George N. Wong https://orcid.org/0000-0001-6952-2147

Qingwen Wu

(吴庆文) https://orcid.org/0000-0003-4773-4987

Paul Yamaguchi https://orcid.org/0000-0002-6017-8199

Doosoo Yoon https://orcid.org/0000-0001-8694-8166

André Young https://orcid.org/0000-0003-0000-2682

Ken Young https://orcid.org/0000-0002-3666-4920

Ziri Younsi https://orcid.org/0000-0001-9283-1191

Feng Yuan (袁峰) https://orcid.org/0000-0003-3564-6437

Ye-Fei Yuan

(袁业飞) https://orcid.org/0000-0002-7330-4756

J. Anton Zensus https://orcid.org/0000-0001-7470-3321

Shuo Zhang https://orcid.org/0000-0002-2967-790X

Guang-Yao Zhao https://orcid.org/0000-0002-4417-1659

Shan-Shan Zhao

(赵杉杉) https://orcid.org/0000-0002-9774-3606

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The EHT Collaboration et al.,

Kazunori Akiyama¹,²,³ ID, Antxon Alberdi⁴ ID, Walter Alef⁵, Juan Carlos Algaba⁶ ID, Richard Anantua³,⁷,⁸ ID, Keiichi Asada⁹ ID, Rebecca Azulay¹⁰,¹¹,⁵ ID, Uwe Bach⁵ ID, Anne-Kathrin Baczko⁵ ID, David Ball¹², Mislav Baloković¹³ ID, John Barrett¹ ID, Michi Bauböck¹⁴ ID, Bradford A. Benson¹⁵,¹⁶ ID, Dan Bintley¹⁷,¹⁸ ID, Lindy Blackburn³,⁷ ID, Raymond Blundell⁷ ID, Katherine L. Bouman¹⁹ ID, Geoffrey C. Bower²⁰,²¹ ID, Hope Boyce²²,²³ ID, Michael Bremer²⁴ ID, Christiaan D. Brinkerink²⁵ ID, Roger Brissenden³,⁷ ID, Silke Britzen⁵ ID, Avery E. Broderick²⁶,²⁷,²⁸ ID, Dominique Broguiere²⁴ ID, Thomas Bronzwaer²⁵ ID, Sandra Bustamante²⁹ ID, Do-Young Byun³⁰,³¹ ID, John E. Carlstrom³²,¹⁶,³³,³⁴ ID, Chiara Ceccobello³⁵ ID, Andrew Chael³⁶,³⁷ ID, Chi-kwan Chan¹²,³八,³⁹ ID, Koushik Chatterjee³,⁷ ID, Shami Chatterjee⁴⁰ ID, Ming-Tang Chen²⁰ ID, Yongjun Chen (陈永军)⁴¹,⁴² ID, Xiaopeng Cheng³⁰ ID, Ilje Cho⁴ ID, Pierre Christian⁴³ ID, Nicholas S. Conroy⁴⁴,⁷ ID, John E. Conway³⁵ ID, James M. Cordes⁴⁰ ID, Thomas M. Crawford¹⁶,³² ID, Geoffrey B. Crew¹ ID, Alejandro Cruz-Osorio⁴⁵ ID, Yuzhu Cui (崔玉竹)⁴⁶,⁴⁷,⁴⁸ ID, Jordy Davelaar⁴⁹,⁵⁰,²⁵ ID, Mariafelia De Laurentis⁵¹,⁴⁵,⁵² ID, Roger Deane⁵³,⁵⁴,⁵⁵ ID, Jessica Dempsey¹⁷,¹十八,⁵⁶ ID, Gregory Desvignes⁵,⁵⁷ ID, Jason Dexter⁵⁸ ID, Vedant Dhruv¹⁴ ID, Sheperd S. Doeleman³,⁷ ID, Sean Dougal¹² ID, Sergio A. Dzib²⁴,⁵ ID, Ralph P. Eatough⁵⁹,⁵ ID, Razieh Emami⁷ ID, Heino Falcke²⁵ ID, Joseph Farah⁶⁰,⁶¹ ID, Vincent L. Fish¹ ID, Ed Fomalont⁶² ID, H. Alyson Ford¹² ID, Raquel Fraga-Encinas²⁵ ID, William T. Freeman⁶³,⁶⁴ ID, Per Friberg¹⁷,¹十八 ID, Christian M. Fromm⁶⁵,⁴⁵,⁵ ID, Antonio Fuentes⁴ ID, Peter Galison³,⁶⁶,⁶⁷ ID, Charles F. Gammie¹⁴,⁴⁴,⁶⁸ ID, Roberto García²⁴ ID, Olivier Gentaz²⁴ ID, Boris Georgiev²⁷,²⁸,²⁶ ID, Ciriaco Goddi⁶⁹,⁷⁰ ID, Roman Gold⁷¹,⁴⁵ ID, Arturo I. Gómez-Ruiz⁷²,⁷³ ID, José L. Gómez⁴ ID, Minfeng Gu (顾敏峰)⁴¹,⁷⁴ ID, Mark Gurwell⁷ ID, Kazuhiro Hada⁴⁷,⁴⁸ ID, Daryl Haggard²²,²³ ID, Kari Haworth⁷, Michael H. Hecht¹ ID, Ronald Hesper⁷⁵ ID, Dirk Heumann¹² ID, Luis C. Ho (何子山)⁷⁶,⁷⁷ ID, Paul Ho⁹,¹十八 ID, Mareki Honma⁴⁷,⁴⁸,⁷⁸ ID, Chih-Wei L. Huang⁹ ID, Lei Huang (黄磊)⁴¹,⁷⁴ ID, David H. Hughes⁷² ID, Shiro Ikeda²,⁷⁹,⁸⁰,⁸¹ ID, C. M. Violette Impellizzeri⁸²,⁶² ID, Makoto Inoue⁹ ID, Sara Issaoun⁷,³⁷ ID, David J. James⁸³ ID, Buell T. Jannuzi¹² ID, Michael Janssen⁵ ID, Britton Jeter⁹ ID, Wu Jiang (江悟)⁴¹ ID, Alejandra Jiménez-Rosales²⁵ ID, Michael D. Johnson³,⁷ ID, Svetlana Jorstad⁸⁴ ID, Abhishek V. Joshi¹⁴ ID, Taehyun Jung³⁰,³¹ ID, Mansour Karami²⁶,²⁷ ID, Ramesh Karuppusamy⁵ ID, Tomohisa Kawashima⁸⁵ ID, Garrett K. Keating⁷ ID, Mark Kettenis⁸⁶ ID, Dong-Jin Kim⁵ ID, Jae-Young Kim⁸⁷,³⁰,⁵ ID, Jongsoo Kim³⁰ ID, Junhan Kim¹²,¹⁹ ID, Motoki Kino²,⁸⁸ ID, Jun Yi Koay⁹ ID, Prashant Kocherlakota⁴⁵ ID, Yutaro Kofuji⁴⁷,⁷⁸ ID, Patrick M. Koch⁹ ID, Shoko Koyama⁸⁹,⁹ ID, Carsten Kramer²⁴ ID, Michael Kramer⁵ ID, Thomas P. Krichbaum⁵ ID, Cheng-Yu Kuo⁹⁰,⁹ ID, Noemi La Bella²⁵ ID, Tod R. Lauer⁹¹ ID, Daeyoung Lee¹⁴ ID, Sang-Sung Lee³⁰ ID, Po Kin Leung⁹² ID, Aviad Levis¹⁹ ID, Zhiyuan Li (李志远)⁹³,⁹⁴ ID, Rocco Lico⁴,⁹⁵ ID, Greg Lindahl⁷ ID, Michael Lindqvist³⁵ ID, Mikhail Lisakov⁵ ID, Jun Liu (刘俊)⁵ ID, Kuo Liu⁵ ID, Elisabetta Liuzzo⁹⁶ ID, Wen-Ping Lo⁹,⁹⁷ ID, Andrei P. Lobanov⁵ ID, Laurent Loinard⁹⁸,⁹⁹ ID, Colin J. Lonsdale¹ ID, Ru-Sen Lu (路如森)⁴¹,⁴²,⁵ ID, Jirong Mao (毛基荣)¹⁰⁰,¹⁰¹,¹⁰² ID, Nicola Marchili⁹,⁶,⁵ ID, Sera Markoff¹⁰³,¹⁰⁴ ID, Daniel P. Marrone¹² ID, Alan P. Marscher⁸⁴ ID, Iván Martí-Vidal¹⁰,¹¹ ID, Satoki Matsushita⁹ ID, Lynn D. Matthews¹ ID, Lia Medeiros¹⁰⁵,¹⁰⁶,¹² ID, Karl M. Menten⁵ ID, Daniel Michalik¹⁰⁷,¹¹⁶ ID, Izumi Mizuno¹⁷,¹十八 ID, Yosuke Mizuno⁴⁶,¹⁰⁸,⁴⁵ ID, James M. Moran³,⁷ ID, Kotaro Moriyama⁴⁵,¹,⁴⁷ ID, Monika Moscibrodzka²⁵ ID, Cornelia Müller⁵,²⁵ ID, Alejandro Mus¹⁰,¹¹ ID, Gibwa Musoke¹⁰³,²⁵ ID, Ioannis Myserlis¹⁰⁹ ID, Andrew Nadolski⁴⁴ ID, Hiroshi Nagai²,⁴⁸ ID, Neil M. Nagar¹¹⁰ ID, Masanori Nakamura¹¹¹,⁹ ID, Ramesh Narayan³,⁷ ID, Gopal Narayanan²⁹ ID, Iniyan Natarajan⁵³,¹¹² ID, Antonios Nathanail⁴⁵,¹¹³ ID, Santiago Navarro Fuentes¹⁰⁹ ID, Joey Neilsen¹¹⁴ ID, Roberto Neri²⁴ ID, Chunchong Ni²⁷,²⁸,²⁶ ID, Aristeidis Noutsos⁵ ID, Michael A. Nowak¹¹⁵ ID, Junghwan Oh¹¹⁶ ID, Hiroki Okino⁴⁷,⁷⁸ ID, Héctor Olivares²⁵ ID, Gisela N. Ortiz-León⁹⁹,⁵ ID, Tomoaki Oyama⁴⁷ ID, Feryal Özel¹² ID, Daniel C. M. Palumbo³,⁷ ID, Georgios Filippos Paraschos⁵ ID, Jongho Park⁹,¹¹⁷ ID, Harriet Parsons¹⁷,¹十八 ID, Nimesh Patel⁷ ID, Ue-Li Pen⁹,²⁶,¹¹⁸,¹¹⁹,¹²⁰ ID, Dominic W. Pesce⁷,³ ID, Vincent Piétu²⁴, Richard Plambeck¹²¹ ID, Aleksandar PopStefanija²⁹ ID, Oliver Porth¹⁰³,⁴⁵ ID, Felix M. Pötzl¹²²,⁵ ID, Ben Prather¹⁴ ID, Jorge A. Preciado-López²⁶ ID, Dimitrios Psaltis¹² ID, Hung-Yi Pu¹²³,¹²⁴,⁹ ID, Venkatessh Ramakrishnan¹¹⁰,¹²⁵,¹²⁶ ID, Ramprasad Rao⁷ ID, Mark G. Rawlings¹²⁷,¹⁷,¹⁸ ID, Alexander W. Raymond³,⁷ ID, Luciano Rezzolla⁴⁵,¹²⁸,¹²⁹ ID, Angelo Ricarte³,⁷ ID, Bart Ripperda¹³⁰,⁵⁰ ID, Greek Roelofs³,⁷,²⁵ ID, Alan Rogers¹ ID, Eduardo Ros⁵ ID, Cristina Romero-Cañizales⁹ ID, Arash Roshanineshat¹² ID, Helge Rottmann⁵ ID, Alan L. Roy⁵ ID, Ignacio Ruiz¹⁰⁹ ID, Chet Ruszczyk¹ ID, Kazi L. J. Rygl⁹⁶ ID, Salvador Sánchez¹⁰⁹ ID, David Sánchez-Argüelles⁷²,⁷³ ID, Miguel Sánchez-Portal¹⁰⁹ ID, Mahito Sasada¹³¹,⁴⁷,¹³² ID, Kaushik Satapathy¹² ID, Tuomas Savolainen¹³³,¹²⁶,⁵ ID, F. Peter Schloerb²⁹ ID, Jonathan Schonfeld⁷ ID, Karl-Friedrich Schuster²⁴ ID, Lijing Shao⁷⁷,⁵ ID, Zhiqiang Shen (沈志强)⁴¹,⁴² ID, Des Small⁸⁶ ID, Bong Won Sohn¹⁷,¹十八,³⁰,³¹,¹³⁴ ID, Jason SooHoo¹ ID, Kamal Souccar²⁹ ID, He Sun (孙赫)¹⁹ ID, Fumie Tazaki⁴⁷ ID, Alexandra J. Tetarenko¹³⁵,³⁷ ID, Paul Tiede⁷,³ ID, Remo P. J. Tilanus¹²,²⁵,⁸²,¹³⁶ ID, Michael Titus¹ ID, Pablo Torne¹⁰⁹,⁵ ID, Efthalia Traianou⁴,⁵ ID, Tyler Trent¹² ID, Sascha Trippe¹³⁷ ID, Matthew Turk⁴⁴ ID, Ilse van Bemmel⁸⁶ ID, Huib Jan van Langevelde⁸⁶,⁸²,¹³⁸ ID, Daniel R. van Rossum²⁵ ID, Jesse Vos²⁵ ID, Jan Wagner⁵ ID, Derek Ward-Thompson¹³⁹ ID, John Wardle¹⁴⁰ ID, Jonathan Weintroub³,⁷ ID, Norbert Wex⁵ ID, Robert Wharton⁵ ID, Maciek Wielgus⁵ ID, Kaj Wiik¹⁴¹ ID, Gunther Witzel⁵ ID, Michael F. Wondrak²⁵,¹⁴² ID, George N. Wong¹⁰⁶,¹⁴³ ID, Qingwen Wu
(吳庆文)¹⁴⁴ Ⓓ, Paul Yamaguchi⁷ Ⓓ, Doosoo Yoon¹⁰³ Ⓓ, André Young²⁵ Ⓓ, Ken Young⁷ Ⓓ, Ziri Younsi¹⁴⁵,⁴⁵ Ⓓ, Feng Yuan (袁峰)⁴¹,⁷⁴,¹⁴⁶ Ⓓ, Ye-Fei Yuan (袁业飞)¹⁷,¹⁸,¹⁴⁷ Ⓓ, J. Anton Zensus⁵ Ⓓ, Shuo Zhang¹⁴⁸ Ⓓ, Guang-Yao Zhao⁴ Ⓓ, and

Shan-Shan Zhao (赵杉杉)⁴¹ Ⓓ

¹ Massachusetts Institute of Technology Haystack Observatory, 99 Millstone Road, Westford, MA 01886, USA

²National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan

³Black Hole Initiative at Harvard University, 20 Garden Street, Cambridge, MA 02138, USA

⁴Instituto de Astrofísica de Andalucía-CSIC, Glorieta de la Astronomía s/n, E-18008 Granada, Spain

⁵Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany

⁶Department of Physics, Faculty of Science, Universiti Malaya, 50603 Kuala Lumpur, Malaysia

⁷Center for Astrophysics, Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 02138, USA

⁸Department of Physics & Astrophysics, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA

⁹Institute of Astronomy and Astrophysics, Academia Sinica, 11F of Astronomy-Mathematics Building, AS/NTU No. 1, Section 4, Roosevelt Rd., Taipei 10617, Taiwan, R.O.C.

¹⁰Departament d'Astronomia i Astrofísica, Universitat de València, C. Dr. Moliner 50, E-46100 Burjassot, València, Spain

¹¹Observatori Astronòmic, Universitat de València, C. Catedrático José Beltrán 2, E-46980 Paterna, València, Spain

¹²Steward Observatory and Department of Astronomy, University of Arizona, 933 N. Cherry Ave., Tucson, AZ 85721, USA

¹³Yale Center for Astronomy & Astrophysics, Yale University, 52 Hillhouse Avenue, New Haven, CT 06511, USA

¹⁴Department of Physics, University of Illinois, 1110 West Green Street, Urbana, IL 61801, USA

¹⁵Fermi National Accelerator Laboratory, MS209, P.O. Box 500, Batavia, IL 60510, USA

¹⁶Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637, USA

¹⁷East Asian Observatory, 660 N. A'ohoku Place, Hilo, HI 96720, USA

¹⁸James Clerk Maxwell Telescope (JCMT), 660 N. A'ohoku Place, Hilo, HI 96720, USA

¹⁹California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA

²⁰Institute of Astronomy and Astrophysics, Academia Sinica, 645 N. A'ohoku Place, Hilo, HI 96720, USA

²¹Department of Physics and Astronomy, University of Hawaii at Manoa, 2505 Correa Road, Honolulu, HI 96822, USA

²²Department of Physics, McGill University, 3600 rue University, Montréal, QC H3A 2T8, Canada

²³McGill Space Institute, McGill University, 3550 rue University, Montréal, QC H3A 2A7, Canada

²⁴Institut de Radioastronomie Millimétrique (IRAM), 300 rue de la Piscine, F-38406 Saint Martin d'Hères, France

²⁵Department of Astrophysics, Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud University, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands

²⁶Perimeter Institute for Theoretical Physics, 31 Caroline Street N, Waterloo, ON N2L 2Y5, Canada

²⁷Department of Physics and Astronomy, University of Waterloo, 200 University Avenue W, Waterloo, ON N2L 3G1, Canada

²⁸Waterloo Centre for Astrophysics, University of Waterloo, Waterloo, ON N2L 3G1, Canada

²⁹Department of Astronomy, University of Massachusetts, 01003, Amherst, MA, USA

³⁰Korea Astronomy and Space Science Institute, Daedok-daero 776, Yuseong-gu, Daejeon 34055, Republic of Korea

³¹University of Science and Technology, Gajeong-ro 217, Yuseong-gu, Daejeon 34113, Republic of Korea

³²Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637, USA

³³Department of Physics, University of Chicago, 5720 South Ellis Avenue, Chicago, IL 60637, USA

³⁴Enrico Fermi Institute, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637, USA

³⁵Department of Space, Earth and Environment, Chalmers University of Technology, Onsala Space Observatory, SE-43992 Onsala, Sweden

³⁶Princeton Center for Theoretical Science, Jadwin Hall, Princeton University, Princeton, NJ 08544, USA

³⁷NASA Hubble Fellowship Program, Einstein Fellow

³⁸Data Science Institute, University of Arizona, 1230 N. Cherry Ave., Tucson, AZ 85721, USA

³⁹Program in Applied Mathematics, University of Arizona, 617 N. Santa Rita, Tucson, AZ 85721, USA

⁴⁰Cornell Center for Astrophysics and Planetary Science, Cornell University, Ithaca, NY 14853, USA

⁴¹Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030, People's Republic of China

⁴²Key Laboratory of Radio Astronomy, Chinese Academy of Sciences, Nanjing 210008, People's Republic of China

⁴³Physics Department, Fairfield University, 1073 North Benson Road, Fairfield, CT 06824, USA

⁴⁴Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801, USA

⁴⁵Institut für Theoretische Physik, Goethe-Universität Frankfurt, Max-von-Laue-Straße 1, D-60438 Frankfurt am Main, Germany

⁴⁶Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shengrong Road 520, Shanghai, 201210, People's Republic of China

⁴⁷Mizusawa VLBI Observatory, National Astronomical Observatory of Japan, 2-12 Hoshigaoka, Mizusawa, Oshu, Iwate 023-0861, Japan

⁴⁸Department of Astronomical Science, The Graduate University for Advanced Studies (SOKENDAI), 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan

⁴⁹Department of Astronomy and Columbia Astrophysics Laboratory, Columbia University, 550 W. 120th Street, New York, NY 10027, USA

⁵⁰Center for Computational Astrophysics, Flatiron Institute, 162 Fifth Avenue, New York, NY 10010, USA

⁵¹Dipartimento di Fisica “E. Pancini,” Università di Napoli “Federico II,” Compl. Univ. di Monte S. Angelo, Edificio G, Via Cinthia, I-80126, Napoli, Italy

⁵²INFN Sez. di Napoli, Compl. Univ. di Monte S. Angelo, Edificio G, Via Cinthia, I-80126, Napoli, Italy

⁵³Wits Centre for Astrophysics, University of the Witwatersrand, 1 Jan Smuts Avenue, Braamfontein, Johannesburg 2050, South Africa

⁵⁴Department of Physics, University of Pretoria, Hatfield, Pretoria 0028, South Africa

⁵⁵Centre for Radio Astronomy Techniques and Technologies, Department of Physics and Electronics, Rhodes University, Makhanda 6140, South Africa

⁵⁶ASTRON, Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands

⁵⁷LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 place Jules Janssen, F-92195 Meudon, France

⁵⁸JILA and Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309, USA

⁵⁹National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing 100101, People's Republic of China

⁶⁰Las Cumbres Observatory, 6740 Cortona Drive, Suite 102, Goleta, CA 93117-5575, USA

⁶¹Department of Physics, University of California, Santa Barbara, CA 93106-9530, USA

⁶²National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903, USA

⁶³Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 32-D476, 77 Massachusetts Ave., Cambridge, MA 02142, USA

⁶⁴Google Research, 355 Main St., Cambridge, MA 02142, USA

⁶⁵Institut für Theoretische Physik und Astrophysik, Universität Würzburg, Emil-Fischer-Str. 31, D-97074 Würzburg, Germany

⁶⁶Department of History of Science, Harvard University, Cambridge, MA 02138, USA

⁶⁷Department of Physics, Harvard University, Cambridge, MA 02138, USA

⁶⁸NCSA, University of Illinois, 1205 W. Clark St., Urbana, IL 61801, USA
<footnote n="69">⁶⁹ Dipartimento di Fisica, Università degli Studi di Cagliari, SP Monserrato-Sestu km 0.7, I-09042 Monserrato, Italy</footnote>

<footnote n="70">⁷⁰ INAF—Osservatorio Astronomico di Cagliari, Via della Scienza 5, I-09047, Selargius, CA, Italy</footnote>

<footnote n="71">⁷¹ CP3-Origins, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark</footnote>

<footnote n="72">⁷² Instituto Nacional de Astrofísica, Óptica y Electrónica. Apartado Postal 51 y 216, 72000. Puebla Pue., México</footnote>

<footnote n="73">⁷³ Consejo Nacional de Ciencia y Tecnología, Av. Insurgentes Sur 1582, 03940, Ciudad de México, México</footnote>

<footnote n="74">⁷⁴ Key Laboratory for Research in Galaxies and Cosmology, Chinese Academy of Sciences, Shanghai 200030, People's Republic of China</footnote>

<footnote n="75">⁷⁵ NOVA Sub-mm Instrumentation Group, Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen, The Netherlands</footnote>

<footnote n="76">⁷⁶ Department of Astronomy, School of Physics, Peking University, Beijing 100871, People's Republic of China</footnote>

<footnote n="77">⁷⁷ Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, People's Republic of China</footnote>

<footnote n="78">⁷⁸ Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan</footnote>

<footnote n="79">⁷⁹ The Institute of Statistical Mathematics, 10-3 Midori-cho, Tachikawa, Tokyo, 190-8562, Japan</footnote>

<footnote n="80">⁸⁰ Department of Statistical Science, The Graduate University for Advanced Studies (SOKENDAI), 10-3 Midori-cho, Tachikawa, Tokyo 190-8562, Japan</footnote>

<footnote n="81">⁸¹ Kavli Institute for the Physics and Mathematics of the Universe, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, 277-8583, Japan</footnote>

<footnote n="82">⁸² Leiden Observatory, Leiden University, Postbus 2300, 9513 RA Leiden, The Netherlands</footnote>

<footnote n="83">⁸³ ASTRAVEO LLC, P.O. Box 1668, Gloucester, MA 01931, USA</footnote>

<footnote n="84">⁸⁴ Institute for Astrophysical Research, Boston University, 725 Commonwealth Ave., Boston, MA 02215, USA</footnote>

<footnote n="85">⁸⁵ Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8582, Japan</footnote>

<footnote n="86">⁸⁶ Joint Institute for VLBI ERIC (JIVE), Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands</footnote>

<footnote n="87">⁸⁷ Department of Astronomy and Atmospheric Sciences, Kyungpook National University, Daegu 702-701, Republic of Korea</footnote>

<footnote n="88">⁸⁸ Kogakuin University of Technology & Engineering, Academic Support Center, 2665-1 Nakano, Hachioji, Tokyo 192-0015, Japan</footnote>

<footnote n="89">⁸⁹ Niigata University, 8050 Ikarashi-nino-cho, Nishi-ku, Niigata 950-2181, Japan</footnote>

<footnote n="90">⁹⁰ Physics Department, National Sun Yat-Sen University, No. 70, Lien-Hai Road, Kaosiung City 80424, Taiwan, R.O.C.</footnote>

<footnote n="91">⁹¹ National Optical Astronomy Observatory, 950 N. Cherry Ave., Tucson, AZ 85719, USA</footnote>

<footnote n="92">⁹² Department of Physics, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong</footnote>

<footnote n="93">⁹³ School of Astronomy and Space Science, Nanjing University, Nanjing 210023, People's Republic of China</footnote>

<footnote n="94">⁹⁴ Key Laboratory of Modern Astronomy and Astrophysics, Nanjing University, Nanjing 210023, People's Republic of China</footnote>

<footnote n="95">⁹⁵ INAF-Istituto di Radioastronomia, Via P. Gobetti 101, I-40129 Bologna, Italy</footnote>

<footnote n="96">⁹⁶ INAF-Istituto di Radioastronomia & Italian ALMA Regional Centre, Via P. Gobetti 101, I-40129 Bologna, Italy</footnote>

<footnote n="97">⁹⁷ Department of Physics, National Taiwan University, No.1, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan, R.O.C.</footnote>

<footnote n="98">⁹⁸ Instituto de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, Morelia 58089, México</footnote>

<footnote n="99">⁹⁹ Instituto de Astronomía, Universidad Nacional Autónoma de México (UNAM), Apdo Postal 70-264, Ciudad de México, México</footnote>

<footnote n="100">¹⁰⁰ Yunnan Observatories, Chinese Academy of Sciences, 650011 Kunming, Yunnan Province, People's Republic of China</footnote>

<footnote n="101">¹⁰¹ Center for Astronomical Mega-Science, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing, 100012, People's Republic of China</footnote>

<footnote n="102">¹⁰² Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, 650011 Kunming, People's Republic of China</footnote>

<footnote n="103">¹⁰³ Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands</footnote>

<footnote n="104">¹⁰⁴ Gravitation and Astroparticle Physics Amsterdam (GRAPPA) Institute, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands</footnote>

<footnote n="105">¹⁰⁵ NSF Astronomy and Astrophysics Postdoctoral Fellow</footnote>

<footnote n="106">¹⁰⁶ School of Natural Sciences, Institute for Advanced Study, 1 Einstein Drive, Princeton, NJ 08540, USA</footnote>

<footnote n="107">¹⁰⁷ Science Support Office, Directorate of Science, European Space Research and Technology Centre (ESA/ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands</footnote>

<footnote n="108">¹⁰⁸ School of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, People's Republic of China</footnote>

<footnote n="109">¹⁰⁹ Institut de Radioastronomie Millimétrique (IRAM), Avenida Divina Pastora 7, Local 20, E-18012, Granada, Spain</footnote>

<footnote n="110">¹¹⁰ Astronomy Department, Universidad de Concepción, Casilla 160-C, Concepción, Chile</footnote>

<footnote n="111">¹¹¹ National Institute of Technology, Hachinohe College, 16-1 Uwanotai, Tamonoki, Hachinohe City, Aomori 039-1192, Japan</footnote>

<footnote n="112">¹¹² South African Radio Astronomy Observatory, Observatory 7925, Cape Town, South Africa</footnote>

<footnote n="113">¹¹³ Department of Physics, National and Kapodistrian University of Athens, Panepistimiopolis, GR 15783 Zografos, Greece</footnote>

<footnote n="114">¹¹⁴ Department of Physics, Villanova University, 800 Lancaster Avenue, Villanova, PA 19085, USA</footnote>

<footnote n="115">¹¹⁵ Physics Department, Washington University CB 1105, St. Louis, MO 63130, USA</footnote>

<footnote n="116">¹¹⁶ Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul, Republic of Korea</footnote>

<footnote n="117">¹¹⁷ EACOA Fellow</footnote>

<footnote n="118">¹¹⁸ Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George Street, Toronto, ON M5S 3H8, Canada</footnote>

<footnote n="119">¹¹⁹ Dunlap Institute for Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4, Canada</footnote>

<footnote n="120">¹²⁰ Canadian Institute for Advanced Research, 180 Dundas St. W, Toronto, ON M5G 1Z8, Canada</footnote>

<footnote n="121">¹²¹ Radio Astronomy Laboratory, University of California, Berkeley, CA 94720, USA</footnote>

<footnote n="122">¹²² Department of Physics, University College Cork, Kane Building, College Road, Cork T12 K8AF, Ireland</footnote>

<footnote n="123">¹²³ Department of Physics, National Taiwan Normal University, No. 88, Sec. 4, Tingzhou Rd., Taipei 116, Taiwan, R.O.C.</footnote>

<footnote n="124">¹²⁴ Center of Astronomy and Gravitation, National Taiwan Normal University, No. 88, Sec. 4, Tingzhou Road, Taipei 116, Taiwan, R.O.C.</footnote>

<footnote n="125">¹²⁵ Finnish Centre for Astronomy with ESO, FI-20014 University of Turku, Finland</footnote>

<footnote n="126">¹²⁶ Aalto University Metsähovi Radio Observatory, Metsähovintie 114, FI-02540 Kylmälä, Finland</footnote>

<footnote n="127">¹²⁷ Gemini Observatory/NSF NOIRLab, 670 N. A'ohōkū Place, Hilo, HI 96720, USA</footnote>

<footnote n="128">¹²⁸ Frankfurt Institute for Advanced Studies, Ruth-Moufang-Strasse 1, D-60438 Frankfurt, Germany</footnote>

<footnote n="129">¹²⁹ School of Mathematics, Trinity College, Dublin 2, Ireland</footnote>

<footnote n="130">¹³⁰ Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544, USA</footnote>

<footnote n="131">¹³¹ Department of Physics, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan</footnote>

<footnote n="132">¹³² Hiroshima Astrophysical Science Center, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan</footnote>

<footnote n="133">¹³³ Aalto University Department of Electronics and Nanoengineering, PL 15500, FI-00076 Aalto, Finland</footnote>

<footnote n="134">¹³⁴ Department of Astronomy, Yonsei University, Yonsei-ro 50, Seodaemun-gu, 03722 Seoul, Republic of Korea</footnote>

<footnote n="135">¹³⁵ Department of Physics and Astronomy, Texas Tech University, Lubbock, TX 79409-1051, USA</footnote>

<footnote n="136">¹³⁶ Netherlands Organisation for Scientific Research (NWO), Postbus 93138, 2509 AC Den Haag, The Netherlands</footnote>

<footnote n="137">¹³⁷ Department of Physics and Astronomy, Seoul National University, Gwanak-gu, Seoul 08826, Republic of Korea</footnote>
¹³⁸ University of New Mexico, Department of Physics and Astronomy, Albuquerque, NM 87131, USA

¹³⁹ Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE, UK

¹⁴⁰ Physics Department, Brandeis University, 415 South Street, Waltham, MA 02453, USA

¹⁴¹ Tuorla Observatory, Department of Physics and Astronomy, University of Turku, Finland

¹⁴² Radboud Excellence Fellow of Radboud University, Nijmegen, The Netherlands

¹⁴³ Princeton Gravity Initiative, Princeton University, Princeton, NJ 08544, USA

¹⁴⁴ School of Physics, Huazhong University of Science and Technology, Wuhan, Hubei 430074, People's Republic of China

¹⁴⁵ Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey, RH5 6NT, UK

¹⁴⁶ School of Astronomy and Space Sciences, University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, People's Republic of China

¹⁴⁷ Astronomy Department, University of Science and Technology of China, Hefei 230026, People's Republic of China

¹⁴⁸ Bard College, 30 Campus Road, Annandale-on-Hudson, NY 12504, USA