First M87 Event Horizon Telescope Results. II. Array and Instrumentation

DOI: 
10.3847/2041-8213/ab0c96
Publication date: 
01/04/2019
Main author: 
Event Horizon Telescope Collaboration
IAA authors: 
Alberdi, Antxon;Gómez, José L.
Authors: 
Event Horizon Telescope Collaboration;Akiyama, Kazunori;Alberdi, Antxon;Alef, Walter;Asada, Keiichi;Azulay, Rebecca;Baczko, Anne-Kathrin;Ball, David;Baloković, Mislav;Barrett, John;Bintley, Dan;Blackburn, Lindy;Boland, Wilfred;Bouman, Katherine L.;Bower, Geoffrey C.;Bremer, Michael;Brinkerink, Christiaan D.;Brissenden, Roger;Britzen, Silke;Broderick, Avery E.;Broguiere, Dominique;Bronzwaer, Thomas;Byun, Do-Young;Carlstrom, John E.;Chael, Andrew;Chan, Chi-kwan;Chatterjee, Shami;Chatterjee, Koushik;Chen, Ming-Tang;Chen, Yongjun;Cho, Ilje;Christian, Pierre;Conway, John E.;Cordes, James M.;Crew, Geoffrey B.;Cui, Yuzhu;Davelaar, Jordy;De Laurentis, Mariafelicia;Deane, Roger;Dempsey, Jessica;Desvignes, Gregory;Dexter, Jason;Doeleman, Sheperd S.;Eatough, Ralph P.;Falcke, Heino;Fish, Vincent L.;Fomalont, Ed;Fraga-Encinas, Raquel;Friberg, Per;Fromm, Christian M.;Gómez, José L.;Galison, Peter;Gammie, Charles F.;García, Roberto;Gentaz, Olivier;Georgiev, Boris;Goddi, Ciriaco;Gold, Roman;Gu, Minfeng;Gurwell, Mark;Hada, Kazuhiro;Hecht, Michael H.;Hesper, Ronald;Ho, Luis C.;Ho, Paul;Honma, Mareki;Huang, Chih-Wei L.;Huang, Lei;Hughes, David H.;Ikeda, Shiro;Inoue, Makoto;Issaoun, Sara;James, David J.;Jannuzi, Buell T.;Janssen, Michael;Jeter, Britton;Jiang, Wu;Johnson, Michael D.;Jorstad, Svetlana;Jung, Taehyun;Karami, Mansour;Karuppusamy, Ramesh;Kawashima, Tomohisa;Keating, Garrett K.;Kettenis, Mark;Kim, Jae-Young;Kim, Junhan;Kim, Jongsoo;Kino, Motoki;Koay, Jun Yi;Koch, Patrick M.;Koyama, Shoko;Kramer, Michael;Kramer, Carsten;Krichbaum, Thomas P.;Kuo, Cheng-Yu;Lauer, Tod R.;Lee, Sang-Sung;Li, Yan-Rong;Li, Zhiyuan;Lindqvist, Michael;Liu, Kuo;Liuzzo, Elisabetta;Lo, Wen-Ping;Lobanov, Andrei P.;Loinard, Laurent;Lonsdale, Colin;Lu, Ru-Sen;MacDonald, Nicholas R.;Mao, Jirong;Markoff, Sera;Marrone, Daniel P.;Marscher, Alan P.;Martí-Vidal, Iván;Matsushita, Satoki;Matthews, Lynn D.;Medeiros, Lia;Menten, Karl M.;Mizuno, Yosuke;Mizuno, Izumi;Moran, James M.;Moriyama, Kotaro;Moscibrodzka, Monika;Müller, Cornelia;Nagai, Hiroshi;Nagar, Neil M.;Nakamura, Masanori;Narayan, Ramesh;Narayanan, Gopal;Natarajan, Iniyan;Neri, Roberto;Ni, Chunchong;Noutsos, Aristeidis;Okino, Hiroki;Olivares, Héctor;Ortiz-León, Gisela N.;Oyama, Tomoaki;Özel, Feryal;Palumbo, Daniel C. M.;Patel, Nimesh;Pen, Ue-Li;Pesce, Dominic W.;Piétu, Vincent;Plambeck, Richard;PopStefanija, Aleksandar;Porth, Oliver;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;Ryan, Benjamin R.;Rygl, Kazi L. J.;Sánchez, Salvador;Sánchez-Arguelles, David;Sasada, Mahito;Savolainen, Tuomas;Schloerb, F. Peter;Schuster, Karl-Friedrich;Shao, Lijing;Shen, Zhiqiang;Small, Des;Sohn, Bong Won;SooHoo, Jason;Tazaki, Fumie;Tiede, Paul;Tilanus, Remo P. J.;Titus, Michael;Toma, Kenji;Torne, Pablo;Trent, Tyler;Trippe, Sascha;Tsuda, Shuichiro;van Bemmel, Ilse;van Langevelde, Huib Jan;van Rossum, Daniel R.;Wagner, Jan;Wardle, John;Weintroub, Jonathan;Wex, Norbert;Wharton, Robert;Wielgus, Maciek;Wong, George N.;Wu, Qingwen;Young, André;Young, Ken;Younsi, Ziri;Yuan, Feng;Yuan, Ye-Fei;Zensus, J. Anton;Zhao, Guangyao;Zhao, Shan-Shan;Zhu, Ziyan;Algaba, Juan-Carlos;Allardi, Alexander;Amestica, Rodrigo;Bach, Uwe;Beaudoin, Christopher;Benson, Bradford A.;Berthold, Ryan;Blanchard, Jay M.;Blundell, Ray;Bustamente, Sandra;Cappallo, Roger;Castillo-Domínguez, Edgar;Chang, Chih-Cheng;Chang, Shu-Hao;Chang, Song-Chu;Chen, Chung-Chen;Chilson, Ryan;Chuter, Tim C.;Córdova Rosado, Rodrigo;Coulson, Iain M.;Crawford, Thomas M.;Crowley, Joseph;David, John;Derome, Mark;Dexter, Matthew;Dornbusch, Sven;Dudevoir, Kevin A.;Dzib, Sergio A.;Eckert, Chris;Erickson, Neal R.;Everett, Wendeline B.;Faber, Aaron;Farah, Joseph R.;Fath, Vernon;Folkers, Thomas W.;Forbes, David C.;Freund, Robert;Gómez-Ruiz, Arturo I.;Gale, David M.;Gao, Feng;Geertsema, Gertie;Graham, David A.;Greer, Christopher H.;Grosslein, Ronald;Gueth, Frédéric;Halverson, Nils W.;Han, Chih-Chiang;Han, Kuo-Chang;Hao, Jinchi;Hasegawa, Yutaka;Henning, Jason W.;Hernández-Gómez, Antonio;Herrero-Illana, Rubén;Heyminck, Stefan;Hirota, Akihiko;Hoge, James;Huang, Yau-De;Impellizzeri, C. M. Violette;Jiang, Homin;Kamble, Atish;Keisler, Ryan;Kimura, Kimihiro;Kono, Yusuke;Kubo, Derek;Kuroda, John;Lacasse, Richard;Laing, Robert A.;Leitch, Erik M.;Li, Chao-Te;Lin, Lupin C. -C.;Liu, Ching-Tang;Liu, Kuan-Yu;Lu, Li-Ming;Marson, Ralph G.;Martin-Cocher, Pierre L.;Massingill, Kyle D.;Matulonis, Callie;McColl, Martin P.;McWhirter, Stephen R.;Messias, Hugo;Meyer-Zhao, Zheng;Michalik, Daniel;Montaña, Alfredo;Montgomerie, William;Mora-Klein, Matias;Muders, Dirk;Nadolski, Andrew;Navarro, Santiago;Nguyen, Chi H.;Nishioka, Hiroaki;Norton, Timothy;Nystrom, George;Ogawa, Hideo;Oshiro, Peter;Oyama, Tomoaki;Padin, Stephen;Parsons, Harriet;Paine, Scott N.;Peñalver, Juan;Phillips, Neil M.;Poirier, Michael;Pradel, Nicolas;Primiani, Rurik A.;Raffin, Philippe A.;Rahlin, Alexandra S.;Reiland, George;Risacher, Christopher;Ruiz, Ignacio;Sáez-Madaín, Alejandro F.;Sassella, Remi;Schellart, Pim;Shaw, Paul;Silva, Kevin M.;Shiokawa, Hotaka;Smith, David R.;Snow, William;Souccar, Kamal;Sousa, Don;Sridharan, T. K.;Srinivasan, Ranjani;Stahm, William;Stark, Antony A.;Story, Kyle;Timmer, Sjoerd T.;Vertatschitsch, Laura;Walther, Craig;Wei, Ta-Shun;Whitehorn, Nathan;Whitney, Alan R.;Woody, David P.;Wouterloot, Jan G. A.;Wright, Melvin;Yamaguchi, Paul;Yu, Chen-Yu;Zeballos, Milagros;Ziurys, Lucy
Journal: 
The Astrophysical Journal Letters
Refereed: 
Yes
Publication type: 
Article
Volume: 
875
Pages: 
L2
Abstract: 
The Event Horizon Telescope (EHT) is a very long baseline interferometry (VLBI) array that comprises millimeter- and submillimeter-wavelength telescopes separated by distances comparable to the diameter of the Earth. At a nominal operating wavelength of ∼1.3 mm, EHT angular resolution (λ/D) is ∼25 μas, which is sufficient to resolve nearby supermassive black hole candidates on spatial and temporal scales that correspond to their event horizons. With this capability, the EHT scientific goals are to probe general relativistic effects in the strong-field regime and to study accretion and relativistic jet formation near the black hole boundary. In this Letter we describe the system design of the EHT, detail the technology and instrumentation that enable observations, and provide measures of its performance. Meeting the EHT science objectives has required several key developments that have facilitated the robust extension of the VLBI technique to EHT observing wavelengths and the production of instrumentation that can be deployed on a heterogeneous array of existing telescopes and facilities. To meet sensitivity requirements, high-bandwidth digital systems were developed that process data at rates of 64 gigabit s<SUP>−1</SUP>, exceeding those of currently operating cm-wavelength VLBI arrays by more than an order of magnitude. Associated improvements include the development of phasing systems at array facilities, new receiver installation at several sites, and the deployment of hydrogen maser frequency standards to ensure coherent data capture across the array. These efforts led to the coordination and execution of the first Global EHT observations in 2017 April, and to event-horizon-scale imaging of the supermassive black hole candidate in M87.
Database: 
ADS
SCOPUS
URL: 
https://www.scopus.com/inward/record.uri?eid=2-s2.0-85064442259&doi=10.3847%2f2041-8213%2fab0c96&partnerID=40&md5=c938a40f94fcc3a5c53c905840363bef
ADS Bibcode: 
2019ApJ...875L...2E
Keywords: 
black hole physics;galaxies: individual: M87;Galaxy: center;gravitational lensing: strong;instrumentation: interferometers;techniques: high angular resolution