Abstract

In 2017, the Event Horizon Telescope (EHT) Collaboration succeeded in capturing the first direct image of the center of the M87 galaxy. The asymmetric ring morphology and size are consistent with theoretical expectations for a weakly accreting supermassive black hole of mass ∼6.5 × 10⁹ M☉. The EHTC also partnered with several international facilities in space and on the ground, to arrange an extensive, quasi-simultaneous multi-wavelength campaign. This Letter presents the results and analysis of this campaign, as well as the multi-wavelength data as a legacy data repository. We captured M87 in a historically low state, and the core flux dominates over HST-1 at high energies, making it possible to combine core flux constraints with the more spatially precise very long baseline interferometry data. We present the most complete simultaneous multi-wavelength spectrum of the active nucleus to date, and discuss the complexity and caveats of combining data from different spatial scales into one broadband spectrum. We apply two heuristic, isotropic leptonic single-zone models to provide insight into the basic source properties, but conclude that a structured jet is necessary to explain M87’s spectrum. We can exclude that the simultaneous γ-ray emission is produced via inverse Compton emission in the same region producing the EHT mm-band emission, and further conclude that the γ-rays can only be produced in the inner jets (inward of HST-1) if there are strongly particle-dominated regions. Direct synchrotron emission from accelerated protons and secondaries cannot yet be excluded.

Collaborations

The Event Horizon Telescope Collaboration236

Kazunori Akiyama21,39,40, Antxon Alberdi41, Walter Alef20, Richard Anantua18,40,42, Rebecca Azulay20,43,44, Anne-Kathrin Baczko20, David Ball45, John Barrett39, Dan Bintley46, Bradford A. Benson47,48, Lindy Blackburn18,40, Raymond Blundell18, Wilfred Boland49, Katherine L. Bouman18,40,50, Geoffrey C. Bower51, Hope Boyce13,14, Michael Bremer52, Christiaan D. Brinkerink11, Roger Brissenden18,40, Silke Britzen20, Avery E. Broderick53,54,55, Dominique Broguiere52, Thomas Bronzwaer11, Do-Young Byun19,56, John E. Carlstrom48,57,58,59, Andrew Chael60,237, Chi-kwan Chan45,61, Shami Chatterjee62, Koushik Chatterjee63, Ming-Tang Chen51, Yongjun Chen (陈永军)25,26, Paul M. Chesler40, Ilje Cho19,56, Pierre Christian64, John E. Conway65, James M. Cordes62, Thomas M. Crawford48,57, Geoffrey B. Crew39, Alejandro Cruz-Osorio66, Jordy Davelaar11,42,67, Mariafelicia De Laurentis66,68,69, Roger Deane70,71,72, Jessica Dempsey46, Gregory Desvignes73, Jason Dexter74, Sheperd S. Doeleman18,40, Ralph P. Eatough20,75, Heino Falcke11, Joseph Farah18,40,76, Vincent L. Fish39, Ed Fomalont77, H. Alyson Ford78, Raquel Fraga-Encinas11, Per Friberg46, Christian M. Fromm18,40,66, Antonio Fuentes41, Peter Galison40,79,80, Charles F. Gammie81,82, Roberto García52, Olivier Gentaz52, Boris Georgiev54,55, Roman Gold53,83, José L. Gómez41, Arturo I. Gómez-Ruiz84,85, Minfeng Gu (顾敏峰)25,86, Mark Gurwell18, Michael H. Hecht39, Ronald Hesper87, Luis C. Ho (何子山)88,89, Paul Ho3, Mareki Honma7,8,90, Chih-Wei L. Huang3, Lei Huang (黄磊)25,86, David H. Hughes84, Shiro Ikeda21,91,92,93, Makoto Inoue3, Sara Issaoun11, David J. James18,40, Buell T. Jannuzi45, Michael Janssen20, Britton Jeter54,55, Wu Jiang (江悟)25, Alejandra Jiménez-Rosales11, Michael D. Johnson18,40, Taehyun Jung19,56, Mansour Karami53,54, Ramesh Karuppusamy20, Mark Kettenis94, Dong-Jin Kim20, Jongsoo Kim19, Junhan Kim45,50, Jun Yi Koay3, Yutaro Kofuji8,90, Patrick M. Koch3, Shoko Koyama3, Michael Kramer20, Carsten Kramer52, Cheng-Yu Kuo3,95, Tod R. Lauer96, Aviad Levis50, Yan-Rong Li (李彦荣)97, Zhiyuan Li (李志远)98,99, Michael Lindqvist65, Rocco Lico41,20, Greg Lindahl18, Jun Liu (刘俊)20, Kuo Liu20, Elisabetta Liuzzo100, Wen-Ping Lo3,101, Andrei P. Lobanov20, Laurent Loinard102,103, Colin Lonsdale39, Nicholas R. MacDonald20, Jirong Mao (毛基荣)104,105,106, Nicola Marchili20,100, Daniel P. Marrone45, Alan P. Marscher15, Iván Martí-Vidal43,44, Satoki Matsushita3, Lynn D. Matthews39, Lia Medeiros45,107, Karl M. Menten20, Izumi Mizuno46, Yosuke Mizuno108,66, James M. Moran18,40, Kotaro Moriyama8,39, Monika Moscibrodzka11, Cornelia Müller11,20, Gibwa Musoke11,63, Alejandro Mus Mejías43,44, Hiroshi Nagai7,21, Neil M. Nagar34, Masanori Nakamura3,109, Ramesh Narayan18,40, Gopal Narayanan110, Iniyan Natarajan70,72,111, Antonios Nathanail66,112, Roberto Neri52, Chunchong Ni54,55, Aristeidis Noutsos20, Hiroki Okino8,90, Héctor Olivares11, Gisela N. Ortiz-León20, Tomoaki Oyama8, Feryal Özel45, Daniel C. M. Palumbo18,40, Nimesh Patel18, Ue-Li Pen53,113,114,115, Dominic W. Pesce18,40, Vincent Piétu52, Richard Plambeck116, Aleksandar PopStefanija110, Oliver Porth63,66, Felix M. Pötzl20, Ben Prather81, Jorge A. Preciado-López53, Dimitrios Psaltis45, Hung-Yi Pu3,53,117, Ramprasad Rao18, Mark G. Rawlings46, Alexander W. Raymond18,40, Luciano Rezzolla118,119,120, Angelo Ricarte18,40, Bart Ripperda42,121, Freek Roelofs11, Alan Rogers39, Eduardo Ros20, Mel Rose45, Arash Roshanineshat45, Helge Rottmann20, Alan L. Roy20, Chet Ruszczyk39, Kazi L. J. Rygl100, Salvador Sánchez122, David Sánchez-Arguelles84,85, Tuomas Savolainen20,123,124, F. Peter Schloerb110, Karl-Friedrich Schuster52, Lijing Shao20,89, Zhiqiang Shen (沈志强)25,26, Des Small94, Bong Won Sohn19,56,125, Jason SooHoo39, He Sun (孙赫)50, Fumie Tazaki8, Alexandra J. Tetarenko46, Paul Tiede54,55, Remo P. J. Tilanus11,12,45,126, Michael Titus39, Kenji Toma127,128, Pablo Torne20,122, Tyler Trent45, Efthalia Traianou20, Sascha Trippe31, Ilse van Bemmel94, Huib Jan van Langevelde94,129, Daniel R. van Rossum11, Jan Wagner20, Derek Ward-Thompson130, John Wardle131, Jonathan Weintroub18,40, Norbert Wex20, Robert Wharton20, Maciek Wielgus18,40, George N. Wong81, Qingwen Wu (吴庆文)132, Doosoo Yoon63, André Young11, Ken Young18, Ziri Younsi133,66,238, Feng Yuan (袁峰)25,86,134, Ye-Fei Yuan (袁业飞)135, J. Anton Zensus20, Guang-Yao Zhao41, Shan-Shan Zhao25

The Fermi Large Area Telescope Collaboration

G. Principe10,32,33, M. Giroletti10, F. D’Ammando10, M. Orienti10

H.E.S.S. Collaboration

H. Abdalla6, R. Adam136, F. Aharonian137,138,139, F. Ait Benkhali138, E. O. Angüner140, C. Arcaro6,*, C. Armand141, T. Armstrong142, H. Ashkar143, M. Backes6,144, V. Baghmanyan145, V. Barbosa Martins146, A. Barnacka147, M. Barnard6, Y. Becherini148, D. Berge146, K. Bernlöhr138, B. Bi149, M. Böttcher6, C. Boisson150, J. Bolmont151, M. de Bony de Lavergne141, M. Breuhaus138, F. Brun143, P. Brun143, M. Bryan152, M. Büchele153, T. Bulik154, T. Bylund148, S. Caroff151, A. Carosi141, S. Casanova145,138, T. Chand6, A. Chen155, G. Cotter142, M. Curyło154, J. Damascene Mbarubucyeye146, I. D. Davids144, J. Davies142, C. Deil138, J. Devin156, P. deWilt157, L. Dirson158, A. Djannati-Ataï159, A. Dmytriiev150, A. Donath138, V. Doroshenko149, C. Duffy160, J. Dyks161, K. Egberts162, F. Eichhorn153, S. Einecke157, G. Emery151, J.-P. Ernenwein140, K. Feijen157, S. Fegan136, A. Fiasson141, G. Fichet de Clairfontaine150, G. Fontaine136, S. Funk153, M. Füßling146, S. Gabici159, Y. A. Gallant163, G. Giavitto146, L. Giunti143,159, D. Glawion153,*, J. F. Glicenstein143, D. Gottschall149, M.-H. Grondin156, J. Hahn138, M. Haupt146, G. Hermann138, J. A. Hinton138, W. Hofmann138, C. Hoischen162, T. L. Holch164, M. Holler165, M. Hörbe142, D. Horns158, D. Huber165, M. Jamrozy147, D. Jankowsky153, F. Jankowsky166, A. Jardin-Blicq138, V. Joshi153, I. Jung-Richardt153, E. Kasai144, M. A. Kastendieck158, K. Katarzyński167, U. Katz153, D. Khangulyan168, B. Khélifi159, S. Klepser146, W. Kluźniak161, Nu. Komin155, R. Konno146, K. Kosack143, D. Kostunin146, M. Kreter6, G. Lamanna141, A. Lemière159, M. Lemoine-Goumard156, J.-P. Lenain151, C. Levy151, T. Lohse164, I. Lypova146, J. Mackey137, J. Majumdar146, D. Malyshev149, D. Malyshev153, V. Marandon138, P. Marchegiani155, A. Marcowith163, A. Mares156, G. Martí-Devesa165, R. Marx166,138, G. Maurin141, P. J. Meintjes169, M. Meyer153, R. Moderski161, M. Mohamed166, L. Mohrmann153, A. Montanari143, C. Moore160, P. Morris142, E. Moulin143, J. Muller136, T. Murach146, K. Nakashima153, A. Nayerhoda145, M. de Naurois136, H. Ndiyavala6, F. Niederwanger165, J. Niemiec145, L. Oakes164, P. O’Brien160, H. Odaka170, S. Ohm146, L. Olivera-Nieto138, E. de Ona Wilhelmi146, M. Ostrowski147, M. Panter138, S. Panny165, R. D. Parsons164, G. Peron138, B. Peyaud143, Q. Piel141, S. Pita159, V. Poireau141, A. Priyana Noel147, D. A. Prokhorov152, H. Prokoph146, G. Pühlhofer149,*, M. Punch148,159, A. Quirrenbach166, R. Rauth165, P. Reichherzer143, A. Reimer165, O. Reimer165, Q. Remy138, M. Renaud163, F. Rieger138, L. Rinchiuso143, C. Romoli138, G. Rowell157, B. Rudak161, E. Ruiz-Velasco138, V. Sahakian171, S. Sailer138, D. A. Sanchez141,*, A. Santangelo149, M. Sasaki153, M. Scalici149, H. M. Schutte6, U. Schwanke164, S. Schwemmer166, M. Seglar-Arroyo143, M. Senniappan148, A. S. Seyffert6, N. Shafi155, K. Shiningayamwe144, R. Simoni152, A. Sinha159, H. Sol150, A. Specovius153, S. Spencer142, M. Spir-Jacob159, Ł. Stawarz147, L. Sun152, R. Steenkamp144, C. Stegmann146,162, S. Steinmassl138, C. Steppa162, T. Takahashi172, T. Tavernier143, A. M. Taylor146, R. Terrier159, D. Tiziani153, M. Tluczykont158, L. Tomankova153, C. Trichard136, M. Tsirou163, R. Tuffs138, Y. Uchiyama168, D. J. van der Walt6, C. van Eldik153, C. van Rensburg6, B. van Soelen169, G. Vasileiadis163, J. Veh153, C. Venter6, P. Vincent151, J. Vink152, H. J. Völk138, T. Vuillaume141, Z. Wadiasingh6, S. J. Wagner166, J. Watson142, F. Werner138, R. White138, A. Wierzcholska145,166, Yu Wun Wong153, A. Yusafzai153, M. Zacharias6,150, R. Zanin138, D. Zargaryan137,139, A. A. Zdziarski161, A. Zech150, S. J. Zhu146, J. Zorn138, S. Zouari159, N. Żywucka6

MAGIC Collaboration

V. A. Acciari173, S. Ansoldi174, L. A. Antonelli175, A. Arbet Engels176, M. Artero177, K. Asano178, D. Baack179, A. Babić180, A. Baquero181, U. Barres de Almeida182, J. A. Barrio181, J. Becerra González173, W. Bednarek183, L. Bellizzi184, E. Bernardini185, M. Bernardos186, A. Berti187, J. Besenrieder188, W. Bhattacharyya185, C. Bigongiari175, A. Biland176, O. Blanch177, G. Bonnoli184, Ž. Bošnjak180, G. Busetto186, R. Carosi189, G. Ceribella188, M. Cerruti190, Y. Chai188, A. Chilingarian191, S. Cikota180, S. M. Colak177, E. Colombo173, J. L. Contreras181, J. Cortina192, S. Covino175, G. D’Amico188, V. D’Elia175, P. Da Vela189,239, F. Dazzi175, A. De Angelis186, B. De Lotto174, M. Delfino177,240, J. Delgado177,240, C. Delgado Mendez192, D. Depaoli187, F. Di Pierro187, L. Di Venere193, E. Do Souto Espiñeira177, D. Dominis Prester194, A. Donini174, D. Dorner195, M. Doro186, D. Elsaesser179, V. Fallah Ramazani196, A. Fattorini179, G. Ferrara175, M. V. Fonseca181, L. Font197, C. Fruck188, S. Fukami178, R. J. García López173, M. Garczarczyk185, S. Gasparyan198, M. Gaug197, N. Giglietto193, F. Giordano193, P. Gliwny183, N. Godinović199, J. G. Green175, D. Green188, D. Hadasch178, A. Hahn188,†, L. Heckmann188, J. Herrera173, J. Hoang181, D. Hrupec200, M. Hütten188, T. Inada178, S. Inoue201, K. Ishio188, Y. Iwamura178, I. Jiménez192, J. Jormanainen196, L. Jouvin177, Y. Kajiwara202, M. Karjalainen173, D. Kerszberg177, Y. Kobayashi178, H. Kubo202, J. Kushida203, A. Lamastra175, D. Lelas199, F. Leone175, E. Lindfors196, S. Lombardi175, F. Longo174,241, R. López-Coto186, M. López-Moya181, A. López-Oramas173, S. Loporchio193, B. Machado de Oliveira Fraga182, C. Maggio197, P. Majumdar204, M. Makariev205, M. Mallamaci186, G. Maneva205, M. Manganaro194, K. Mannheim195, L. Maraschi175, M. Mariotti186, M. Martínez177, D. Mazin178,188,†, S. Menchiari184, S. Mender179, S. Mićanović194, D. Miceli174, T. Miener181, M. Minev205, J. M. Miranda184, R. Mirzoyan188, E. Molina190, A. Moralejo177, D. Morcuende181, V. Moreno197, E. Moretti177, V. Neustroev206, C. Nigro177, K. Nilsson196, K. Nishijima203, K. Noda178, S. Nozaki202, Y. Ohtani178, T. Oka202, J. Otero-Santos173, S. Paiano175, M. Palatiello174, D. Paneque188, R. Paoletti184, J. M. Paredes190, L. Pavletić194, P. Peñil181, C. Perennes186, M. Persic174,242, P. G. Prada Moroni189, E. Prandini186, C. Priyadarshi177, I. Puljak199, W. Rhode179, M. Ribó190, J. Rico177, C. Righi175, A. Rugliancich189, L. Saha181, N. Sahakyan198, T. Saito178, S. Sakurai178, K. Satalecka185, F. G. Saturni175, B. Schleicher195, K. Schmidt179, T. Schweizer188, J. Sitarek183, I. Šnidarić207, D. Sobczynska183, A. Spolon186, A. Stamerra175, D. Strom188, M. Strzys178, Y. Suda188, T. Surić207, M. Takahashi178, F. Tavecchio175, P. Temnikov205, T. Terzić194, M. Teshima178,188, L. Tosti208, S. Truzzi184, A. Tutone175, S. Ubach197, J. van Scherpenberg188, G. Vanzo173, M. Vazquez Acosta173, S. Ventura184, V. Verguilov205, C. F. Vigorito187, V. Vitale209, I. Vovk178, M. Will188, C. Wunderlich184, D. Zarić199

VERITAS Collaboration

C.B. Adams210, W. Benbow18, A. Brill211, M. Capasso210, J. L. Christiansen212, A. J. Chromey213, M. K. Daniel18, M. Errando214, K. A Farrell215, Q. Feng210, J. P. Finley216, L. Fortson217, A. Furniss218, A. Gent219, C. Giuri220, T. Hassan220, O. Hervet221, J. Holder222, G. Hughes18, T. B. Humensky211, W. Jin223,‡, P. Kaaret224, M. Kertzman225, D. Kieda226, S. Kumar13, M. J. Lang227, M. Lundy13, G. Maier220, P. Moriarty227, R. Mukherjee210, D. Nieto228, M. Nievas-Rosillo220, S. O’Brien13, R. A. Ong229, A. N. Otte219, S. Patel224, K. Pfrang220, M. Pohl230, R. R. Prado220, E. Pueschel220, J. Quinn215, K. Ragan13, P. T. Reynolds231, D. Ribeiro211, G. T. Richards222, E. Roache18, C. Rulten217, J. L. Ryan229, M. Santander223,‡, G. H. Sembroski216, R. Shang229, A. Weinstein213, D. A. Williams221, T. J Williamson222

EAVN Collaboration

Tomoya Hirota7,21, Lang Cui26,232, Kotaro Niinuma233, Hyunwook Ro19,125, Nobuyuki Sakai19, Satoko Sawada-Satoh233, Kiyoaki Wajima19, Na Wang26,232, Xiang Liu26,232, Yoshinori Yonekura234

1Department of Physics, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia 2Department of Physics, Villanova University, 800 E. Lancaster Avenue, Villanova, PA 19085, USA 3Institute of Astronomy and Astrophysics, Academia Sinica, 11F of Astronomy-Mathematics Building, AS/NTU No. 1, Sec. 4, Roosevelt Rd, Taipei 10617, Taiwan, R.O.C. 4Yale Center for Astronomy & Astrophysics, 52 Hillhouse Avenue, New Haven, CT 06511, USA 5Department of Physics, Yale University, P.O. Box 2018120, New Haven, CT 06520, USA 6Centre for Space Research, North-West University, Potchefstroom 2520, South Africa 7Department of Astronomical Science, The Graduate University for Advanced Studies (SOKENDAI), 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan 8Mizusawa VLBI Observatory, 2-12 Hoshigaoka, Mizusawa, Oshu, Iwate 023-0861, Japan 9525 Davey Laboratory, Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802, USA 10INAF Istituto di Radioastronomia, Via P. Gobetti, 101, I-40129 Bologna, Italy 11Department of Astrophysics, Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud University, P.O. Box 9010, 6500 GL Nijmegen, The Netherlands 12Leiden Observatory—Allegro, Leiden University, P.O. Box 9513, 2300 RA Leiden, The Netherlands 13Department of Physics, McGill University, 3600 University Street, Montréal, QC H3A 2T8, Canada 14McGill Space Institute, McGill University, 3550 University Street, Montréal, QC H3A 2A7, Canada 15Institute for Astrophysical Research, Boston University, 725 Commonwealth Avenue, Boston, MA 02215, USA 16Astronomical Institute, St. Petersburg University, Universitetskij Pr. 28, Petrodvorets, 198504 St. Petersburg, Russia 17Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8582, Japan 18Center for Astrophysics, Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 02138, USA 19Korea Astronomy and Space Science Institute, Daedeok-daero 776, Yuseong-gu, Daejeon 34055, Republic of Korea 20Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn, Germany 21National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan 22Kogakuin University of Technology & Engineering, Academic Support Center, 2665-1 Nakano, Hachioji, Tokyo 192-0015, Japan 23Moscow Institute of Physics and Technology, Institutsky per. 9, Moscow region, Dolgoprudny, 141700, Russia 24Astro Space Center, Lebedev Physical Institute, Profsouznaya 84/32, Moscow 117997, Russia 25Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai 200030, People’s Republic of China 26Key Laboratory of Radio Astronomy, Chinese Academy of Sciences, Nanjing 210008, People’s Republic of China 27API—Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands 28GRAPPA—Gravitation and AstroParticle Physics Amsterdam, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands 29Physics Department, Washington University CB 1105, St Louis, MO 63130, USA 30Institute of Astronomy and Astrophysics, Academia Sinica, P.O. Box 23-141, Taipei 10617, Taiwan 31Department of Physics and Astronomy, Seoul National University, Gwanak-gu, Seoul 08826, Republic of Korea 32Dipartimento di Fisica, Universitá di Trieste, I-34127 Trieste, Italy 33Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, I-34127 Trieste, Italy 34Astronomy Department, Universidad de Concepción, Casilla 160-C, Concepción, Chile 35University of Michigan, 1085 S. University Ave., Ann Arbor, MI 48109, USA 36Hiroshima Astrophysical Science Center, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan 37Saint Petersburg State University, 7/9, Universitetskaya nab., St. Petersburg, 199034, Russia 38Special Astrophysical Observatory, Russian Academy of Science, Nizhnii Arkhyz 369167, Russia 39Massachusetts Institute of Technology Haystack Observatory, 99 Millstone Road, Westford, MA 01886, USA 40Black Hole Initiative at Harvard University, 20 Garden Street, Cambridge, MA 02138, USA 41Instituto de Astrofísica de Andalucía-CSIC, Glorieta de la Astronomía s/n, E-18008 Granada, Spain 42Center for Computational Astrophysics, Flatiron Institute, 162 Fifth Avenue, New York, NY 10010, USA 43Departament d’Astronomia i Astrofísica, Universitat de València, C. Dr. Moliner 50, E-46100 Burjassot, València, Spain 44Observatori Astronòmic, Universitat de València, C. Catedrático José Beltrán 2, E-46980 Paterna, València, Spain 45Steward Observatory and Department of Astronomy, University of Arizona, 933 N. Cherry Ave., Tucson, AZ 85721, USA 46East Asian Observatory, 660 N. A’ohoku Place, Hilo, HI 96720, USA 47Fermi National Accelerator Laboratory, MS209, P.O. Box 500, Batavia, IL 60510, USA 48Department of Astronomy and Astrophysics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637, USA 49Nederlandse Onderzoekschool voor Astronomie (NOVA), P.O. Box 9513, 2300 RA Leiden, The Netherlands 50California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125, USA 51Institute of Astronomy and Astrophysics, Academia Sinica, 645 N. A’ohoku Place, Hilo, HI 96720, USA 52Institut de Radioastronomie Millimétrique, 300 rue de la Piscine, F-38406 Saint Martin d’Hères, France 53Perimeter Institute for Theoretical Physics, 31 Caroline Street North, Waterloo, ON, N2L 2Y5, Canada 54Department of Physics and Astronomy, University of Waterloo, 200 University Avenue West, Waterloo, ON, N2L 3G1, Canada 55Waterloo Centre for Astrophysics, University of Waterloo, Waterloo, ON N2L 3G1 Canada 56University of Science and Technology, Gajeong-ro 217, Yuseong-gu, Daejeon 34113, Republic of Korea 57Kavli Institute for Cosmological Physics, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637, USA 58Department of Physics, University of Chicago, 5720 South Ellis Avenue, Chicago, IL 60637, USA 59Enrico Fermi Institute, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637, USA 60Princeton Center for Theoretical Science, Jadwin Hall, Princeton University, Princeton, NJ 08544, USA 61Data Science Institute, University of Arizona, 1230 N. Cherry Ave., Tucson, AZ 85721, USA 62Cornell Center for Astrophysics and Planetary Science, Cornell University, Ithaca, NY 14853, USA 63Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands 64Physics Department, Fairfield University, 1073 North Benson Road, Fairfield, CT 06824, USA 65Department of Space, Earth and Environment, Chalmers University of Technology, Onsala Space Observatory, SE-43992 Onsala, Sweden 66Institut für Theoretische Physik, Goethe-Universität Frankfurt, Max-von-Laue-Straße 1, D-60438 Frankfurt am Main, Germany 67Department of Astronomy and Columbia Astrophysics Laboratory, Columbia University, 550 W 120th Street, New York, NY 10027, USA 68Dipartimento di Fisica “E. Pancini”, Universitá di Napoli “Federico II,” Compl. Univ. di Monte S. Angelo, Edificio G, Via Cinthia, I-80126, Napoli, Italy 69INFN Sez. di Napoli, Compl. Univ. di Monte S. Angelo, Edificio G, Via Cinthia, I-80126, Napoli, Italy 70Wits Centre for Astrophysics, University of the Witwatersrand, 1 Jan Smuts Avenue, Braamfontein, Johannesburg 2050, South Africa 71Department of Physics, University of Pretoria, Hatfield, Pretoria 0028, South Africa 72Centre for Radio Astronomy Techniques and Technologies, Department of Physics and Electronics, Rhodes University, Makhanda 6140, South Africa 73LESIA, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, Université de Paris, 5 place Jules Janssen, F-92195 Meudon, France 74JILA and Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309, USA 75National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing 100101, People’s Republic of China 76University of Massachusetts Boston, 100 William T. Morrissey Boulevard, Boston, MA 02125, USA 77National Radio Astronomy Observatory, 520 Edgemont Rd, Charlottesville, VA 22903, USA 78Steward Observatory and Department of Astronomy, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721, USA 79Department of History of Science, Harvard University, Cambridge, MA 02138, USA 80Department of Physics, Harvard University, Cambridge, MA 02138, USA 81Department of Physics, University of Illinois, 1110 West Green Street, Urbana, IL 61801, USA 82Department of Astronomy, University of Illinois at Urbana-Champaign, 1002 West Green Street, Urbana, IL 61801, USA 83CP3-Origins, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark 84Instituto Nacional de Astrofísica, Óptica y Electrónica. Apartado Postal 51 y 216, 72000. Puebla Pue., México 85Consejo Nacional de Ciencia y Tecnología, Av. Insurgentes Sur 1582, 03940, Ciudad de México, México 86Key Laboratory for Research in Galaxies and Cosmology, Chinese Academy of Sciences, Shanghai 200030, People’s Republic of China 87NOVA Sub-mm Instrumentation Group, Kapteyn Astronomical Institute, University of Groningen, Landleven 12, 9747 AD Groningen, The Netherlands 88Department of Astronomy, School of Physics, Peking University, Beijing 100871, People’s Republic of China 89Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871, People’s Republic of China 90Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan 91The Institute of Statistical Mathematics, 10-3 Midori-cho, Tachikawa, Tokyo, 190-8562, Japan 92Department of Statistical Science, The Graduate University for Advanced Studies (SOKENDAI), 10-3 Midori-cho, Tachikawa, Tokyo 190-8562, Japan 93Kavli Institute for the Physics and Mathematics of the Universe, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, 277-8583, Japan 94Joint Institute for VLBI ERIC (JIVE), Oude Hoogeveensedijk 4, 7991 PD Dwingeloo, The Netherlands 95Physics Department, National Sun Yat-Sen University, No. 70, Lien-Hai Rd, Kaosiung City 80424, Taiwan, R.O.C 96National Optical Astronomy Observatory, 950 North Cherry Ave., Tucson, AZ 85719, USA 97Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, 19B Yuquan Road, Shijingshan District, Beijing, People’s Republic of China 98School of Astronomy and Space Science, Nanjing University, Nanjing 210023, People’s Republic of China 99Key Laboratory of Modern Astronomy and Astrophysics, Nanjing University, Nanjing 210023, People’s Republic of China 100Italian ALMA Regional Centre, INAF-Istituto di Radioastronomia, Via P. Gobetti 101, I-40129 Bologna, Italy 101Department of Physics, National Taiwan University, No.1, Sect.4, Roosevelt Rd., Taipei 10617, Taiwan, R.O.C 102Instituto de Radioastronomía y Astrofísica, Universidad Nacional Autónoma de México, Morelia 58089, México 103Instituto de Astronomía, Universidad Nacional Autónoma de México, CdMx 04510, México 104Yunnan Observatories, Chinese Academy of Sciences, 650011 Kunming, Yunnan Province, People’s Republic of China 105Center for Astronomical Mega-Science, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing, 100012, People’s Republic of China 106Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, 650011 Kunming, People’s Republic of China 107School of Natural Sciences, Institute for Advanced Study, 1 Einstein Drive, Princeton, NJ 08540, USA 108Tsung-Dao Lee Institute and School of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai, 200240, People’s Republic of China 109National Institute of Technology, Hachinohe College, 16-1 Uwanotai, Tamonoki, Hachinohe City, Aomori 039-1192, Japan 110Department of Astronomy, University of Massachusetts, 01003, Amherst, MA, USA 111South African Radio Astronomy Observatory, Observatory 7925, Cape Town, South Africa 112Department of Physics, National and Kapodistrian University of Athens, Panepistimiopolis, GR 15783 Zografos, Greece 113Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George Street, Toronto, ON M5S 3H8, Canada 114Dunlap Institute for Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4, Canada 115Canadian Institute for Advanced Research, 180 Dundas St West, Toronto, ON M5G 1Z8, Canada 116Radio Astronomy Laboratory, University of California, Berkeley, CA 94720, USA 117Department of Physics, National Taiwan Normal University, No. 88, Sec. 4, Tingzhou Rd., Taipei 116, Taiwan, R.O.C. 118Institut für Theoretische Physik, Max-von-Laue-Strasse 1, D-60438 Frankfurt, Germany 119Frankfurt Institute for Advanced Studies, Ruth-Moufang-Strasse 1, D-60438 Frankfurt, Germany 120School of Mathematics, Trinity College, Dublin 2, Ireland 121Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544, USA 122Instituto de Radioastronomía Milimétrica, IRAM, Avenida Divina Pastora 7, Local 20, E-18012, Granada, Spain 123Aalto University Department of Electronics and Nanoengineering, PL 15500, FI-00076 Aalto, Finland 124Aalto University Metsähovi Radio Observatory, Metsähovintie 114, FI-02540 Kylmälä, Finland 125Department of Astronomy, Yonsei University, Yonsei-ro 50, Seodaemun-gu, 03722 Seoul, Republic of Korea 126Netherlands Organisation for Scientific Research (NWO), Postbus 93138, 2509 AC Den Haag, The Netherlands 127Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai 980-8578, Japan 128Astronomical Institute, Tohoku University, Sendai 980-8578, Japan 129Leiden Observatory, Leiden University, Postbus 2300, 9513 RA Leiden, The Netherlands 130Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE, UK 131Physics Department, Brandeis University, 415 South Street, Waltham, MA 02453, USA 132School of Physics, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, People’s Republic of China 133Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey, RH5 6NT, UK 134School of Astronomy and Space Sciences, University of Chinese Academy of Sciences, No. 19A Yuquan Road, Beijing 100049, People’s Republic of China 135Astronomy Department, University of Science and Technology of China, Hefei 230026, People’s Republic of China 136Laboratoire Leprince-Ringuet, École Polytechnique, CNRS, Institut Polytechnique de Paris, F-91128 Palaiseau, France 137Dublin Institute for Advanced Studies, 31 Fitzwilliam Place, Dublin 2, Ireland 138Max-Planck-Institut für Kernphysik, P.O. Box 103980, D-69029 Heidelberg, Germany 139High Energy Astrophysics Laboratory, RAU, 123 Hovsep Emin St Yerevan 0051, Armenia 140Aix Marseille Université, CNRS/IN2P3, CPPM, Marseille, France 141Laboratoire d’Annecy de Physique des Particules, Univ. Grenoble Alpes, Univ. Savoie Mont Blanc, CNRS, LAPP, F-74000 Annecy, France 142University of Oxford, Department of Physics, Denys Wilkinson Building, Keble Road, Oxford OX1 3RH, UK 143IRFU, CEA, Université Paris-Saclay, F-91191 Gif-sur-Yvette, France 144University of Namibia, Department of Physics, Private Bag 13301, Windhoek 10005, Namibia 145Instytut Fizyki Ja̧drowej PAN, ul. Radzikowskiego 152, 31-342 Kraków, Poland 146DESY, D-15738 Zeuthen, Germany 147Obserwatorium Astronomiczne, Uniwersytet Jagielloński, ul. Orla 171, 30-244 Kraków, Poland 148Department of Physics and Electrical Engineering, Linnaeus University, SE-351 95 Växjö, Sweden 149Institut für Astronomie und Astrophysik, Universität Tübingen, Sand 1, D-72076 Tübingen, Germany 150Laboratoire Univers et Théories, Observatoire de Paris, Université PSL, CNRS, Université de Paris, F-92190 Meudon, France 151Sorbonne Université, Université Paris Diderot, Sorbonne Paris Cité, CNRS/IN2P3, Laboratoire de Physique Nucléaire et de Hautes Energies, LPNHE, 4 Place Jussieu, F-75252 Paris, France 152GRAPPA, Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands 153Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen Centre for Astroparticle Physics, Erwin-Rommel-Str. 1, D-91058 Erlangen, Germany 154Astronomical Observatory, The University of Warsaw, Al. Ujazdowskie 4, 00-478 Warsaw, Poland 155School of Physics, University of the Witwatersrand, 1 Jan Smuts Avenue, Braamfontein, Johannesburg, 2050 South Africa 156Université Bordeaux, CNRS/IN2P3, Centre d’Études Nucléaires de Bordeaux Gradignan, F-33175 Gradignan, France 157School of Physical Sciences, University of Adelaide, Adelaide 5005, Australia 158Universität Hamburg, Institut für Experimentalphysik, Luruper Chaussee 149, D-22761 Hamburg, Germany 159Université de Paris, CNRS, Astroparticule et Cosmologie, F-75013 Paris, France 160Department of Physics and Astronomy, The University of Leicester, University Road, Leicester, LE1 7RH, UK 161Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences, ul. Bartycka 18, 00-716 Warsaw, Poland 162Institut für Physik und Astronomie, Universität Potsdam, Karl-Liebknecht-Strasse 24/25, D-14476 Potsdam, Germany 163Laboratoire Univers et Particules de Montpellier, Université Montpellier, CNRS/IN2P3, CC 72, Place Eugène Bataillon, F-34095 Montpellier Cedex 5, France 164Institut für Physik, Humboldt-Universität zu Berlin, Newtonstr. 15, D-12489 Berlin, Germany 165Institut für Astro- und Teilchenphysik, Leopold-Franzens-Universität Innsbruck, A-6020 Innsbruck, Austria 166Landessternwarte, Universität Heidelberg, Königstuhl, D-69117 Heidelberg, Germany 167Institute of Astronomy, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Torun, Poland 168Department of Physics, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo 171-8501, Japan 169Department of Physics, University of the Free State, P.O. Box 339, Bloemfontein 9300, South Africa 170Department of Physics, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan 171Yerevan Physics Institute, 2 Alikhanian Brothers St., 375036 Yerevan, Armenia 172Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo Institutes for Advanced Study (UTIAS), The University of Tokyo, 5-1-5 Kashiwa-no-Ha, Kashiwa, Chiba, 277-8583, Japan 173Instituto de Astrofísica de Canarias and Dpto. Astrofísica, Universidad de La Laguna, 38200, La Laguna, Tenerife, Spain 174Università di Udine and INFN Trieste, I-33100 Udine, Italy 175National Institute for Astrophysics (INAF), I-00136 Rome, Italy 176ETH Zürich, CH-8093 Zürich, Switzerland 177Institut de Física d’Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain 178Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan 179Technische Universität Dortmund, D-44221 Dortmund, Germany 180Croatian MAGIC Group: University of Zagreb, Faculty of Electrical Engineering and Computing (FER), 10000 Zagreb, Croatia 181IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain 182Centro Brasileiro de Pesquisas Físicas (CBPF), 22290-180 URCA, Rio de Janeiro (RJ), Brazil 183University of Lodz, Faculty of Physics and Applied Informatics, Department of Astrophysics, 90-236 Lodz, Poland 184Università di Siena and INFN Pisa, I-53100 Siena, Italy 185Deutsches Elektronen-Synchrotron (DESY), D-15738 Zeuthen, Germany 186Università di Padova and INFN, I-35131 Padova, Italy 187INFN MAGIC Group: INFN Sezione di Torino and Università degli Studi di Torino, I-10125 Torino, Italy 188Max-Planck-Institut für Physik, D-80805 München, Germany 189Università di Pisa and INFN Pisa, I-56126 Pisa, Italy 190Universitat de Barcelona, ICCUB, IEEC-UB, E-08028 Barcelona, Spain 191Armenian MAGIC Group: A. Alikhanyan National Science Laboratory, Armenia 192Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, E-28040 Madrid, Spain 193INFN MAGIC Group: INFN Sezione di Bari and Dipartimento Interateneo di Fisica dell’Università e del Politecnico di Bari, I-70125 Bari, Italy 194Croatian MAGIC Group: University of Rijeka, Department of Physics, 51000 Rijeka, Croatia 195Universität Würzburg, D-97074 Würzburg, Germany 196Finnish MAGIC Group: Finnish Centre for Astronomy with ESO, University of Turku, FI-20014 Turku, Finland 197Departament de Física, and CERES-IEEC, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain 198Armenian MAGIC Group: ICRANet-Armenia at NAS RA, Armenia 199Croatian MAGIC Group: University of Split, Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture (FESB), 21000 Split, Croatia 200Croatian MAGIC Group: Josip Juraj Strossmayer University of Osijek, Department of Physics, 31000 Osijek, Croatia 201Japanese MAGIC Group: RIKEN, Wako, Saitama 351-0198, Japan 202Japanese MAGIC Group: Department of Physics, Kyoto University, 606-8502 Kyoto, Japan 203Japanese MAGIC Group: Department of Physics, Tokai University, Hiratsuka, 259-1292 Kanagawa, Japan 204Saha Institute of Nuclear Physics, HBNI, 1/AF Bidhannagar, Salt Lake, Sector-1, Kolkata 700064, India 205Inst. for Nucl. Research and Nucl. Energy, Bulgarian Academy of Sciences, BG-1784 Sofia, Bulgaria 206Finnish MAGIC Group: Astronomy Research Unit, University of Oulu, FI-90014 Oulu, Finland 207Croatian MAGIC Group: Ruÿder Bošković Institute, 10000 Zagreb, Croatia 208INFN MAGIC Group: INFN Sezione di Perugia, I-06123 Perugia, Italy 209INFN MAGIC Group: INFN Roma Tor Vergata, I-00133 Roma, Italy 210Department of Physics and Astronomy, Barnard College, Columbia University, NY 10027, USA 211Physics Department, Columbia University, New York, NY 10027, USA 212Physics Department, California Polytechnic State University, San Luis Obispo, CA 94307, USA 213Department of Physics and Astronomy, Iowa State University, Ames, IA 50011, USA 214Department of Physics, Washington University, St. Louis, MO 63130, USA 215School of Physics, University College Dublin, Belfield, Dublin 4, Ireland 216Department of Physics and Astronomy, Purdue University, West Lafayette, IN 47907, USA 217School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA 218Department of Physics, California State University—East Bay, Hayward, CA 94542, USA 219School of Physics and Center for Relativistic Astrophysics, Georgia Institute of Technology, 837 State Street NW, Atlanta, GA 30332-0430, USA 220DESY, Platanenallee 6, D-15738 Zeuthen, Germany 221Santa Cruz Institute for Particle Physics and Department of Physics, University of California, Santa Cruz, CA 95064, USA 222Department of Physics and Astronomy and the Bartol Research Institute, University of Delaware, Newark, DE 19716, USA 223Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487, USA 224Department of Physics and Astronomy, University of Iowa, Van Allen Hall, Iowa City, IA 52242, USA 225Department of Physics and Astronomy, DePauw University, Greencastle, IN 46135-0037, USA 226Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112, USA 227School of Physics, National University of Ireland Galway, University Road, Galway, Ireland 228Institute of Particle and Cosmos Physics, Universidad Complutense de Madrid, E-28040 Madrid, Spain 229Department of Physics and Astronomy, University of California, Los Angeles, CA 90095, USA 230Institute of Physics and Astronomy, University of Potsdam, D-14476 Potsdam-Golm, Germany and DESY, Platanenallee 6, D-15738 Zeuthen, Germany 231Department of Physical Sciences, Cork Institute of Technology, Bishopstown, Cork, Ireland 232Xinjiang Astronomical Observatory, Chinese Academy of Sciences, Urumqi 830011, People’s Republic of China 233Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yoshida 1677-1, Yamaguchi, Yamaguchi 753-8512, Japan 234Center for Astronomy, Ibaraki University, 2-1-1 Bunkyo, Mito, Ibaraki 310-8512, Japan