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arXiv · 2304.13252

A ring-like accretion structure in M87 connecting its black hole and jet

Ru-Sen Lu·Keiichi Asada·Thomas P. Krichbaum·Jongho Park·Fumie Tazaki·Hung-Yi Pu·Masanori Nakamura·Andrei Lobanov·Kazuhiro Hada·Kazunori Akiyama·Jae-Young Kim·Ivan Marti-Vidal·José L. Gómez·Tomohisa Kawashima·Feng Yuan·Eduardo Ros·Walter Alef·Silke Britzen·Michael Bremer·Avery E. Broderick·Akihiro Doi·Gabriele Giovannini·Marcello Giroletti·Paul T. P. Ho·Mareki Honma·David H. Hughes·Makoto Inoue·Wu Jiang·Motoki Kino·Shoko Koyama·Michael Lindqvist·Jun Liu·Alan P. Marscher·Satoki Matsushita·Hiroshi Nagai·Helge Rottmann·Tuomas Savolainen·Karl-Friedrich Schuster·Zhi-Qiang Shen·Pablo de Vicente·R. Craig Walker·Hai Yang·J. Anton Zensus·Juan Carlos Algaba·Alexander Allardi·Uwe Bach·Ryan Berthold·Dan Bintley·Do-Young Byun·Carolina Casadio·Shu-Hao Chang·Chih-Cheng Chang·Song-Chu Chang·Chung-Chen Chen·Ming-Tang Chen·Ryan Chilson·Tim C. Chuter·John Conway·Geoffrey B. Crew·Jessica T. Dempsey·Sven Dornbusch·Aaron Faber·Per Friberg·Javier González García·Miguel Gómez Garrido·Chih-Chiang Han·Kuo-Chang Han·Yutaka Hasegawa·Ruben Herrero-Illana·Yau-De Huang·Chih-Wei L. Huang·Violette Impellizzeri·Homin Jiang·Hao Jinchi·Taehyun Jung·Juha Kallunki·Petri Kirves·Kimihiro Kimura·Jun Yi Koay·Patrick M. Koch·Carsten Kramer·Alex Kraus·Derek Kubo·Cheng-Yu Kuo·Chao-Te Li·Lupin Chun-Che Lin·Ching-Tang Liu·Kuan-Yu Liu·Wen-Ping Lo·Li-Ming Lu·Nicholas MacDonald·Pierre Martin-Cocher·Hugo Messias·Zheng Meyer-Zhao·Anthony Minter·Dhanya G. Nair·Hiroaki Nishioka·Timothy J. Norton·George Nystrom·Hideo Ogawa

Abstract

The nearby radio galaxy M87 is a prime target for studying black hole accretion and jet formation^{1,2}. Event Horizon Telescope observations of M87 in 2017, at a wavelength of 1.3 mm, revealed a ring-like structure, which was interpreted as gravitationally lensed emission around a central black hole^3. Here we report images of M87 obtained in 2018, at a wavelength of 3.5 mm, showing that the compact radio core is spatially resolved. High-resolution imaging shows a ring-like structure of 8.4_{-1.1}^{+0.5} Schwarzschild radii in diameter, approximately 50% larger than that seen at 1.3 mm. The outer edge at 3.5 mm is also larger than that at 1.3 mm. This larger and thicker ring indicates a substantial contribution from the accretion flow with absorption effects in addition to the gravitationally lensed ring-like emission. The images show that the edge-brightened jet connects to the accretion flow of the black hole. Close to the black hole, the emission profile of the jet-launching region is wider than the expected profile of a black-hole-driven jet, suggesting the possible presence of a wind associated with the accretion flow.

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Ru-Sen Lu, Keiichi Asada, Thomas P. Krichbaum, Jongho Park, Fumie Tazaki, Hung-Yi Pu, Masanori Nakamura, Andrei Lobanov, Kazuhiro Hada, Kazunori Akiyama, Jae-Young Kim, Ivan Marti-Vidal, José L. Gómez, Tomohisa Kawashima, Feng Yuan, Eduardo Ros, Walter Alef, Silke Britzen, Michael Bremer, Avery E. Broderick, Akihiro Doi, Gabriele Giovannini, Marcello Giroletti, Paul T. P. Ho, Mareki Honma, David H. Hughes, Makoto Inoue, Wu Jiang, Motoki Kino, Shoko Koyama, Michael Lindqvist, Jun Liu, Alan P. Marscher, Satoki Matsushita, Hiroshi Nagai, Helge Rottmann, Tuomas Savolainen, Karl-Friedrich Schuster, Zhi-Qiang Shen, Pablo de Vicente, R. Craig Walker, Hai Yang, J. Anton Zensus, Juan Carlos Algaba, Alexander Allardi, Uwe Bach, Ryan Berthold, Dan Bintley, Do-Young Byun, Carolina Casadio, Shu-Hao Chang, Chih-Cheng Chang, Song-Chu Chang, Chung-Chen Chen, Ming-Tang Chen, Ryan Chilson, Tim C. Chuter, John Conway, Geoffrey B. Crew, Jessica T. Dempsey, Sven Dornbusch, Aaron Faber, Per Friberg, Javier González García, Miguel Gómez Garrido, Chih-Chiang Han, Kuo-Chang Han, Yutaka Hasegawa, Ruben Herrero-Illana, Yau-De Huang, Chih-Wei L. Huang, Violette Impellizzeri, Homin Jiang, Hao Jinchi, Taehyun Jung, Juha Kallunki, Petri Kirves, Kimihiro Kimura, Jun Yi Koay, Patrick M. Koch, Carsten Kramer, Alex Kraus, Derek Kubo, Cheng-Yu Kuo, Chao-Te Li, Lupin Chun-Che Lin, Ching-Tang Liu, Kuan-Yu Liu, Wen-Ping Lo, Li-Ming Lu, Nicholas MacDonald, Pierre Martin-Cocher, Hugo Messias, Zheng Meyer-Zhao, Anthony Minter, Dhanya G. Nair, Hiroaki Nishioka, Timothy J. Norton, George Nystrom, Hideo Ogawa. 2023-04-26. A ring-like accretion structure in M87 connecting its black hole and jet. https://doi.org/10.1038/s41586-023-05843-w

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