First M87 Event Horizon Telescope Results. VII. Polarization of the Ring
Journal article, 2021
In 2017 April, the Event Horizon Telescope (EHT) observed the near-horizon region around the supermassive black hole at the core of the M87 galaxy. These 1.3 mm wavelength observations revealed a compact asymmetric ring-like source morphology. This structure originates from synchrotron emission produced by relativistic plasma located in the immediate vicinity of the black hole. Here we present the corresponding linear-polarimetric EHT images of the center of M87. We find that only a part of the ring is significantly polarized. The resolved fractional linear polarization has a maximum located in the southwest part of the ring, where it rises to the level of similar to 15%. The polarization position angles are arranged in a nearly azimuthal pattern. We perform quantitative measurements of relevant polarimetric properties of the compact emission and find evidence for the temporal evolution of the polarized source structure over one week of EHT observations. The details of the polarimetric data reduction and calibration methodology are provided. We carry out the data analysis using multiple independent imaging and modeling techniques, each of which is validated against a suite of synthetic data sets. The gross polarimetric structure and its apparent evolution with time are insensitive to the method used to reconstruct the image. These polarimetric images carry information about the structure of the magnetic fields responsible for the synchrotron emission. Their physical interpretation is discussed in an accompanying publication.
Low-luminosity active galactic nuclei
Galaxies: individual: M87
Active galactic nuclei
Very long baseline interferometry
Radio interferometry
Galaxy accretion disks
Supermassive black holes
Polarimetry
Astronomy data modeling
Author
Kazunori Akiyama
Massachusetts Institute of Technology (MIT)
National Astronomical Observatory of Japan
Harvard University
Juan Carlos Algaba
University of Malaya
Antxon Alberdi
Spanish National Research Council (CSIC)
Walter Alef
Max Planck Society
Richard Anantua
Harvard-Smithsonian Center for Astrophysics
Flatiron Institute
Harvard University
Keiichi Asada
Academia Sinica
Rebecca Azulay
Universitat de Valencia
Max Planck Society
Anne-Kathrin Baczko
Max Planck Society
David Ball
University of Arizona
Mislav Balokovic
Yale University
John Barrett
Massachusetts Institute of Technology (MIT)
Bradford A. Benson
University of Chicago
Fermi National Accelerator Laboratory
Dan Bintley
East Asian Observatory
Lindy Blackburn
Harvard-Smithsonian Center for Astrophysics
Harvard University
Raymond Blundell
Harvard-Smithsonian Center for Astrophysics
Wilfred Boland
Nederlandse Onderzoekschool voor Astronomie (NOVA)
Katherine L. Bouman
Harvard-Smithsonian Center for Astrophysics
California Institute of Technology (Caltech)
Harvard University
Geoffrey C. Bower
Academia Sinica
Hope Boyce
McGill University
Michael Bremer
Institut de Radioastronomie Millimétrique (IRAM)
Christiaan D. Brinkerink
Radboud University
Roger Brissenden
Harvard-Smithsonian Center for Astrophysics
Harvard University
Silke Britzen
Max Planck Society
Avery E. Broderick
University of Waterloo
Perimeter Institute for Theoretical Physics
Dominique Broguiere
Institut de Radioastronomie Millimétrique (IRAM)
Thomas Bronzwaer
Radboud University
Do-Young Byun
University of Science and Technology (UST)
Korea Astronomy and Space Science Institute
John E. Carlstrom
University of Chicago
Andrew Chael
Princeton University
Chi-kwan Chan
University of Arizona
Shami Chatterjee
Cornell University
Koushik Chatterjee
University of Amsterdam
Ming-Tang Chen
Academia Sinica
Yongjun Chen
Chinese Academy of Sciences
Paul M. Chesler
Harvard University
Ilje Cho
University of Science and Technology (UST)
Korea Astronomy and Space Science Institute
Pierre Christian
Fairfield University
John Conway
Chalmers, Space, Earth and Environment, Onsala Space Observatory
James M. Cordes
Cornell University
Thomas M. Crawford
University of Chicago
Geoffrey B. Crew
Massachusetts Institute of Technology (MIT)
Alejandro Cruz-Osorio
Goethe University Frankfurt
Yuzhu Cui
The Graduate University for Advanced Studies (SOKENDAI)
National Astronomical Observatory of Japan
Jordy Davelaar
Columbia University
Radboud University
Flatiron Institute
Mariafelicia De Laurentis
National Institute for Nuclear Physics
Goethe University Frankfurt
University of Naples Federico II
Roger Deane
University of Witwatersrand
Rhodes University
University of Pretoria
Jessica Dempsey
East Asian Observatory
Gregory Desvignes
Paris Descartes University
Jason Dexter
University of Colorado at Boulder
Sheperd S. Doeleman
Harvard-Smithsonian Center for Astrophysics
Harvard University
Ralph P. Eatough
Max Planck Society
Chinese Academy of Sciences
Heino Falcke
Radboud University
Joseph Farah
Harvard-Smithsonian Center for Astrophysics
Harvard University
University of Massachusetts Boston
Vincent L. Fish
Massachusetts Institute of Technology (MIT)
Ed Fomalont
National Radio Astronomy Observatory
H. Alyson Ford
University of Arizona
Raquel Fraga-Encinas
Radboud University
William T. Freeman
Google Inc.
Massachusetts Institute of Technology (MIT)
Per Friberg
East Asian Observatory
Christian M. Fromm
Harvard University
Goethe University Frankfurt
Harvard-Smithsonian Center for Astrophysics
Antonio Fuentes
Spanish National Research Council (CSIC)
Peter Galison
Harvard University
Charles F. Gammie
University of Illinois
Roberto Garcia
Institut de Radioastronomie Millimétrique (IRAM)
Olivier Gentaz
Institut de Radioastronomie Millimétrique (IRAM)
Boris Georgiev
University of Waterloo
Ciriaco Goddi
Leiden University
Radboud University
Roman Gold
Perimeter Institute for Theoretical Physics
University of Southern Denmark
Jose L. Gomez
Spanish National Research Council (CSIC)
Gomez-Ruiz
National Council for Science and Technology Mexico
National Institute of Astrophysics, Optics and Electronics
Minfeng Gu
Chinese Academy of Sciences
Mark Gurwell
Harvard-Smithsonian Center for Astrophysics
Kazuhiro Hada
National Astronomical Observatory of Japan
The Graduate University for Advanced Studies (SOKENDAI)
Daryl Haggard
McGill University
Michael H. Hecht
Massachusetts Institute of Technology (MIT)
Ronald Hesper
University of Groningen
Luis C. Ho
Beijing University of Technology
Paul Ho
Academia Sinica
Mareki Honma
National Astronomical Observatory of Japan
University of Tokyo
The Graduate University for Advanced Studies (SOKENDAI)
Chih-Wei L. Huang
Academia Sinica
Lei Huang
Chinese Academy of Sciences
David H. Hughes
National Institute of Astrophysics, Optics and Electronics
Shiro Ikeda
The Graduate University for Advanced Studies (SOKENDAI)
The Institute of Statistical Mathematics
University of Tokyo
National Astronomical Observatory of Japan
Makoto Inoue
Academia Sinica
Sara Issaoun
Radboud University
David J. James
ASTRAVEO
Buell T. Jannuzi
University of Arizona
Michael Janssen
Max Planck Society
Britton Jeter
University of Waterloo
Wu Jiang
Chinese Academy of Sciences
Alejandra Jimenez-Rosales
Radboud University
Michael D. Johnson
Harvard University
Harvard-Smithsonian Center for Astrophysics
Svetlana Jorstad
Boston University
Saint Petersburg State University - Spsu
Taehyun Jung
Korea Astronomy and Space Science Institute
University of Science and Technology (UST)
Mansour Karami
University of Waterloo
Perimeter Institute for Theoretical Physics
Ramesh Karuppusamy
Max Planck Society
Tomohisa Kawashima
University of Tokyo
Garrett K. Keating
Harvard-Smithsonian Center for Astrophysics
Mark Kettenis
Joint Institute for VLBI in Europe (JIVE)
Dong-Jin Kim
Max Planck Society
Jae-Young Kim
Korea Astronomy and Space Science Institute
Max Planck Society
Jongsoo Kim
Korea Astronomy and Space Science Institute
Junhan Kim
University of Arizona
California Institute of Technology (Caltech)
Motoki Kino
Kogakuin University of Technology and Engineering
National Astronomical Observatory of Japan
Jun Yi Koay
Academia Sinica
Yutaro Kofuji
University of Tokyo
National Astronomical Observatory of Japan
Patrick M. Koch
Academia Sinica
Shoko Koyama
Academia Sinica
Michael Kramer
Max Planck Society
Carsten Kramer
Institut de Radioastronomie Millimétrique (IRAM)
Thomas P. Krichbaum
Max Planck Society
Cheng-Yu Kuo
Academia Sinica
National Sun Yat-Sen University
Tod R. Lauer
National Optical Astronomy Observatory
Sang-Sung Lee
Korea Astronomy and Space Science Institute
Aviad Levis
California Institute of Technology (Caltech)
Yan-Rong Li
Chinese Academy of Sciences
Zhiyuan Li
Nanjing University
Michael Lindqvist
Chalmers, Space, Earth and Environment, Onsala Space Observatory
Rocco Lico
Max Planck Society
Spanish National Research Council (CSIC)
Greg Lindahl
Harvard-Smithsonian Center for Astrophysics
Jun Liu
Max Planck Society
Kuo Liu
Max Planck Society
Elisabetta Liuzzo
Istituto nazionale di astrofisica (INAF)
Wen-Ping Lo
Academia Sinica
National Taiwan University
Andrei P. Lobanov
Max Planck Society
Laurent Loinard
Universidad Nacional Autónoma de México
Colin Lonsdale
Massachusetts Institute of Technology (MIT)
Ru-Sen Lu
Chinese Academy of Sciences
Max Planck Society
Nicholas R. MacDonald
Max Planck Society
Jirong Mao
Chinese Academy of Sciences
Nicola Marchili
Max Planck Society
Istituto nazionale di astrofisica (INAF)
Sera Markoff
University of Amsterdam
Daniel P. Marrone
University of Arizona
Alan P. Marscher
Boston University
Ivan Marti-Vidal
Universitat de Valencia
Satoki Matsushita
Academia Sinica
Lynn D. Matthews
Massachusetts Institute of Technology (MIT)
Lia Medeiros
University of Arizona
Institute for Advanced Study
Karl M. Menten
Max Planck Society
Izumi Mizuno
East Asian Observatory
Yosuke Mizuno
Goethe University Frankfurt
Shanghai Jiao Tong University
James M. Moran
Harvard University
Harvard-Smithsonian Center for Astrophysics
Kotaro Moriyama
National Astronomical Observatory of Japan
Massachusetts Institute of Technology (MIT)
Monika Moscibrodzka
Radboud University
Cornelia Muller
Radboud University
Max Planck Society
Gibwa Musoke
Radboud University
University of Amsterdam
Alejandro Mus Mejias
Universitat de Valencia
Daniel Michalik
European Space Research and Technology Centre (ESA ESTEC)
University of Chicago
Andrew Nadolski
University of Illinois
Hiroshi Nagai
National Astronomical Observatory of Japan
The Graduate University for Advanced Studies (SOKENDAI)
Neil M. Nagar
University of Concepcion
Masanori Nakamura
National Institute of Technology, Hachinohe College
Academia Sinica
Ramesh Narayan
Harvard University
Harvard-Smithsonian Center for Astrophysics
Gopal Narayanan
University of Massachusetts
Iniyan Natarajan
South African Radio Astronomy Observatory (SARAO)
University of Witwatersrand
Rhodes University
Antonios Nathanail
Goethe University Frankfurt
National and Kapodistrian University of Athens
Joseph Neilsen
Villanova University
Roberto Neri
Institut de Radioastronomie Millimétrique (IRAM)
Chunchong Ni
University of Waterloo
Aristeidis Noutsos
Max Planck Society
Michael A. Nowak
Washington University in St. Louis
Hiroki Okino
University of Tokyo
National Astronomical Observatory of Japan
Hector Olivares
Radboud University
Gisela N. Ortiz-Leon
Max Planck Society
Tomoaki Oyama
National Astronomical Observatory of Japan
Feryal Ozel
University of Arizona
Daniel C. M. Palumbo
Harvard-Smithsonian Center for Astrophysics
Harvard University
Jongho Park
Academia Sinica
Nimesh Patel
Harvard-Smithsonian Center for Astrophysics
Ue-Li Pen
University of Toronto
Perimeter Institute for Theoretical Physics
Canadian Institute for Advanced Research
Dominic W. Pesce
Harvard-Smithsonian Center for Astrophysics
Harvard University
Vincent Pietu
Institut de Radioastronomie Millimétrique (IRAM)
Richard Plambeck
University of California at Berkeley
Aleksandar PopStefanija
University of Massachusetts
Oliver Porth
University of Amsterdam
Goethe University Frankfurt
Felix M. Poetzl
Max Planck Society
Ben Prather
Harvard University
Jorge A. Preciado-Lopez
Perimeter Institute for Theoretical Physics
Dimitrios Psaltis
University of Arizona
Hung-Yi Pu
Academia Sinica
National Taiwan Normal University
Perimeter Institute for Theoretical Physics
Venkatessh Ramakrishnan
University of Concepcion
Ramprasad Rao
Academia Sinica
Mark G. Rawlings
East Asian Observatory
Alexander W. Raymond
Harvard-Smithsonian Center for Astrophysics
Harvard University
Luciano Rezzolla
Frankfurt Institute for Advanced Studies
Trinity College Dublin
Goethe University Frankfurt
Angelo Ricarte
Harvard University
Harvard-Smithsonian Center for Astrophysics
Bart Ripperda
Princeton University
Flatiron Institute
Freek Roelofs
Radboud University
Alan Rogers
Massachusetts Institute of Technology (MIT)
Eduardo Ros
Max Planck Society
Mel Rose
University of Arizona
Arash Roshanineshat
University of Arizona
Helge Rottmann
Max Planck Society
Alan L. Roy
Max Planck Society
Chet Ruszczyk
Massachusetts Institute of Technology (MIT)
Kazi L. J. Rygl
Istituto nazionale di astrofisica (INAF)
Salvador Sanchez
Institut de Radioastronomie Millimétrique (IRAM)
David Sanchez-Arguelles
National Institute of Astrophysics, Optics and Electronics
National Council for Science and Technology Mexico
Mahito Sasada
National Astronomical Observatory of Japan
Hiroshima University
Tuomas Savolainen
Max Planck Society
Aalto University
F. Peter Schloerb
University of Massachusetts
Karl-Friedrich Schuster
Institut de Radioastronomie Millimétrique (IRAM)
Lijing Shao
Beijing University of Technology
Max Planck Society
Zhiqiang Shen
Chinese Academy of Sciences
Des Small
Joint Institute for VLBI in Europe (JIVE)
Bong Won Sohn
Yonsei University
University of Science and Technology (UST)
Korea Astronomy and Space Science Institute
Jason SooHoo
Massachusetts Institute of Technology (MIT)
He Sun
California Institute of Technology (Caltech)
Fumie Tazaki
National Astronomical Observatory of Japan
Alexandra J. Tetarenko
East Asian Observatory
Paul Tiede
University of Waterloo
Remo P. J. Tilanus
Netherlands Organisation for Scientific Research (NWO)
Leiden University
University of Arizona
Radboud University
Michael Titus
Massachusetts Institute of Technology (MIT)
Kenji Toma
Tohoku University
Pablo Torne
Max Planck Society
Institut de Radioastronomie Millimétrique (IRAM)
Tyler Trent
University of Arizona
Efthalia Traianou
Max Planck Society
Sascha Trippe
Seoul National University
Ilse van Bemmel
Joint Institute for VLBI in Europe (JIVE)
Huib Jan van Langevelde
Joint Institute for VLBI in Europe (JIVE)
Leiden University
Daniel R. van Rossum
Radboud University
Jan Wagner
Max Planck Society
Derek Ward-Thompson
University of Central Lancashire
John Wardle
Brandeis University
Jonathan Weintroub
Harvard-Smithsonian Center for Astrophysics
Harvard University
Norbert Wex
Max Planck Society
Robert Wharton
Max Planck Society
Maciek Wielgus
Harvard-Smithsonian Center for Astrophysics
Harvard University
George N. Wong
University of Illinois
Qingwen Wu
Huazhong University of Science and Technology
Doosoo Yoon
University of Amsterdam
Andre Young
Radboud University
Ken Young
Harvard-Smithsonian Center for Astrophysics
Ziri Younsi
Goethe University Frankfurt
University College London (UCL)
Feng Yuan
Chinese Academy of Sciences
Ye-Fei Yuan
University of Science and Technology of China
J. Anton Zensus
Max Planck Society
Guang-Yao Zhao
Spanish National Research Council (CSIC)
Shan-Shan Zhao
Chinese Academy of Sciences
Astrophysical Journal Letters
2041-8205 (ISSN) 2041-8213 (eISSN)
Vol. 910 1 L12Subject Categories (SSIF 2011)
Astronomy, Astrophysics and Cosmology
Computer Vision and Robotics (Autonomous Systems)
Medical Image Processing
DOI
10.3847/2041-8213/abe71d