Event Horizon Telescope observations of the jet launching and collimation in Centaurus A
Creators: name: Janssen, Michael
name: Falcke, Heino
name: Kadler, Matthias
name: Ros, Eduardo
name: Wielgus, Maciek
name: Akiyama, Kazunori
name: Baloković, Mislav
name: Blackburn, Lindy
name: Bouman, Katherine L.
name: Chael, Andrew
name: Chan, Chi-kwan
name: Chatterjee, Koushik
name: Davelaar, Jordy
name: Edwards, Philip G.
name: Fromm, Christian M.
name: Gómez, José L.
name: Goddi, Ciriaco
name: Issaoun, Sara
name: Johnson, Michael D.
name: Kim, Junhan
name: Koay, Jun Yi
name: Krichbaum, Thomas P.
name: Liu, Jun
name: Liuzzo, Elisabetta
name: Markoff, Sera
name: Markowitz, Alex
name: Marrone, Daniel P.
name: Mizuno, Yosuke
name: Müller, Cornelia
name: Ni, Chunchong
name: Pesce, Dominic W.
name: Ramakrishnan, Venkatessh
name: Roelofs, Freek
name: Rygl, Kazi L. J.
name: van Bemmel, Ilse
name: Alberdi, Antxon
name: Alef, Walter
name: Algaba, Juan Carlos
name: Anantua, Richard
name: Asada, Keiichi
name: Azulay, Rebecca
name: Baczko, Anne-Kathrin
name: Ball, David
name: Barrett, John
name: Benson, Bradford A.
name: Bintley, Dan
name: Blundell, Raymond
name: Boland, Wilfred
name: Bower, Geoffrey C.
name: Boyce, Hope
name: Bremer, Michael
name: Brinkerink, Christiaan D.
name: Brissenden, Roger
name: Britzen, Silke
name: Broderick, Avery E.
name: Broguiere, Dominique
name: Bronzwaer, Thomas
name: Byun, Do-Young
name: Carlstrom, John E.
name: Chatterjee, Shami
name: Chen, Ming-Tang
name: Chen, Yongjun
name: Chesler, Paul M.
name: Cho, Ilje
name: Christian, Pierre
name: Conway, John E.
name: Cordes, James M.
name: Crawford, Thomas M.
name: Crew, Geoffrey B.
name: Cruz-Osorio, Alejandro
name: Cui, Yuzhu
name: De Laurentis, Mariafelicia
name: Deane, Roger
name: Dempsey, Jessica
name: Desvignes, Gregory
name: Dexter, Jason
name: Doeleman, Sheperd S.
name: Eatough, Ralph P.
name: Farah, Joseph
name: Fish, Vincent L.
name: Fomalont, Ed
name: Ford, H. Alyson
name: Fraga-Encinas, Raquel
name: Friberg, Per
name: Fuentes, Antonio
name: Galison, Peter
name: Gammie, Charles F.
name: García, Roberto
name: Gelles, Zachary
name: Gentaz, Olivier
name: Georgiev, Boris
name: Gold, Roman
name: Gómez-Ruiz, Arturo I.
name: Gu, Minfeng
name: Gurwell, Mark
name: Hada, Kazuhiro
name: Haggard, Daryl
name: Hecht, Michael H.
name: Hesper, Ronald
name: Himwich, Elizabeth
name: Ho, Luis C.
name: Ho, Paul
name: Honma, Mareki
name: Huang, Chih-Wei L.
name: Huang, Lei
name: Hughes, David H.
name: Ikeda, Shiro
name: Inoue, Makoto
name: James, David J.
name: Jannuzi, Buell T.
name: Janssen, Michael
name: Jeter, Britton
name: Jiang, Wu
name: Jimenez-Rosales, Alejandra
name: Jorstad, Svetlana
name: Jung, Taehyun
name: Karami, Mansour
name: Karuppusamy, Ramesh
name: Kawashima, Tomohisa
name: Keating, Garrett K.
name: Kettenis, Mark
name: Kim, Dong-Jin
name: Kim, Jae-Young
name: Kim, Jongsoo
name: Kino, Motoki
name: Kofuji, Yutaro
name: Koyama, Shoko
name: Kramer, Michael
name: Kramer, Carsten
name: Kuo, Cheng-Yu
name: Lauer, Tod R.
name: Lee, Sang-Sung
name: Levis, Aviad
name: Li, Yan-Rong
name: Li, Zhiyuan
name: Lindqvist, Michael
name: Lico, Rocco
name: Lindahl, Greg
name: Liu, Kuo
name: Lo, Wen-Ping
name: Lobanov, Andrei P.
name: Loinard, Laurent
name: Lonsdale, Colin
name: Lu, Ru-Sen
name: MacDonald, Nicholas R.
name: Mao, Jirong
name: Marchili, Nicola
name: Marscher, Alan P.
name: Martí-Vidal, Iván
name: Matsushita, Satoki
name: Matthews, Lynn D.
name: Medeiros, Lia
name: Menten, Karl M.
name: Mizuno, Izumi
name: Moran, James M.
name: Moriyama, Kotaro
name: Moscibrodzka, Monika
name: Musoke, Gibwa
name: Mejías, Alejandro Mus
name: Nagai, Hiroshi
name: Nagar, Neil M.
name: Nakamura, Masanori
name: Narayan, Ramesh
name: Narayanan, Gopal
name: Natarajan, Iniyan
name: Nathanail, Antonios
name: Neilsen, Joey
name: Neri, Roberto
name: Noutsos, Aristeidis
name: Nowak, Michael A.
name: Okino, Hiroki
name: Olivares, Héctor
name: Ortiz-León, Gisela N.
name: Oyama, Tomoaki
name: Özel, Feryal
name: Palumbo, Daniel C. M.
name: Park, Jongho
name: Patel, Nimesh
name: Pen, Ue-Li
name: Piétu, Vincent
name: Plambeck, Richard
name: PopStefanija, Aleksandar
name: Porth, Oliver
name: Pötzl, Felix M.
name: Prather, Ben
name: Preciado-López, Jorge A.
name: Psaltis, Dimitrios
name: Pu, Hung-Yi
name: Rao, Ramprasad
name: Rawlings, Mark G.
name: Raymond, Alexander W.
name: Rezzolla, Luciano
name: Ricarte, Angelo
name: Ripperda, Bart
name: Rogers, Alan
name: Rose, Mel
name: Roshanineshat, Arash
name: Rottmann, Helge
name: Roy, Alan L.
name: Ruszczyk, Chet
name: Sánchez, Salvador
name: Sánchez-Arguelles, David
name: Sasada, Mahito
name: Savolainen, Tuomas
name: Schloerb, F. Peter
name: Schuster, Karl-Friedrich
name: Shao, Lijing
name: Shen, Zhiqiang
name: Small, Des
name: Sohn, Bong Won
name: SooHoo, Jason
name: Sun, He
name: Tazaki, Fumie
name: Tetarenko, Alexandra J.
name: Tiede, Paul
name: Tilanus, Remo P. J.
name: Titus, Michael
name: Torne, Pablo
name: Trent, Tyler
name: Traianou, Efthalia
name: Trippe, Sascha
name: van Langevelde, Huib Jan
name: van Rossum, Daniel R.
name: Wagner, Jan
name: Ward-Thompson, Derek
name: Wardle, John
name: Weintroub, Jonathan
name: Wex, Norbert
name: Wharton, Robert
name: Wong, George N.
name: Wu, Qingwen
name: Yoon, Doosoo
name: Young, André
name: Young, Ken
name: Younsi, Ziri
name: Yuan, Feng
name: Yuan, Ye-Fei
name: Zensus, J. Anton
name: Zhao, Guang-Yao
name: Zhao, Shan-Shan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: Very-long-baseline interferometry (VLBI) observations of active galactic nuclei at millimeter wavelengths have the power to reveal the launching and initial collimation region of extragalactic radio jets, down to $10-100$ gravitational radii ($r_g=GM/c^2$) scales in nearby sources. Centaurus A is the closest radio-loud source to Earth. It bridges the gap in mass and accretion rate between the supermassive black holes (SMBHs) in Messier 87 and our galactic center. A large southern declination of $-43^{\circ}$ has however prevented VLBI imaging of Centaurus A below $λ1$cm thus far. Here, we show the millimeter VLBI image of the source, which we obtained with the Event Horizon Telescope at $228$GHz. Compared to previous observations, we image Centaurus A's jet at a tenfold higher frequency and sixteen times sharper resolution and thereby probe sub-lightday structures. We reveal a highly-collimated, asymmetrically edge-brightened jet as well as the fainter counterjet. We find that Centaurus A's source structure resembles the jet in Messier 87 on ${\sim}500r_g$ scales remarkably well. Furthermore, we identify the location of Centaurus A's SMBH with respect to its resolved jet core at $λ1.3$mm and conclude that the source's event horizon shadow should be visible at THz frequencies. This location further supports the universal scale invariance of black holes over a wide range of masses.
description: 27 pages, 9 figures. This is a post-peer-review, pre-copyedit version of an article published in Nature Astronomy. The final authenticated version is available online at: https://doi.org/10.1038/s41550-021-01417-w