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.

Galaxy accretion disks

Low-luminosity active galactic nuclei

Galaxies: individual: M87

Radio interferometry

Very long baseline interferometry

Astronomy data modeling

Supermassive black holes

Active galactic nuclei

Polarimetry

Author

Kazunori Akiyama

Harvard University

Massachusetts Institute of Technology (MIT)

National Astronomical Observatory of Japan

Juan Carlos Algaba

University of Malaya

Antxon Alberdi

Spanish National Research Council (CSIC)

Walter Alef

Max Planck Society

Richard Anantua

Harvard University

Flatiron Institute

Harvard-Smithsonian Center for Astrophysics

Keiichi Asada

Academia Sinica

Rebecca Azulay

Max Planck Society

Universitat de Valencia

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 University

Harvard-Smithsonian Center for Astrophysics

Raymond Blundell

Harvard-Smithsonian Center for Astrophysics

Wilfred Boland

Nederlandse Onderzoekschool voor Astronomie (NOVA)

Katherine L. Bouman

California Institute of Technology (Caltech)

Harvard-Smithsonian Center for Astrophysics

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 University

Harvard-Smithsonian Center for Astrophysics

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

Radboud University

Flatiron Institute

Columbia University

Mariafelicia De Laurentis

Goethe University Frankfurt

University of Naples Federico II

National Institute for Nuclear Physics

Roger Deane

University of Pretoria

University of Witwatersrand

Rhodes University

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

Chinese Academy of Sciences

Max Planck Society

Heino Falcke

Radboud University

Joseph Farah

Harvard-Smithsonian Center for Astrophysics

University of Massachusetts Boston

Harvard University

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

Massachusetts Institute of Technology (MIT)

Google Inc.

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 Institute of Astrophysics, Optics and Electronics

National Council for Science and Technology Mexico

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

University of Tokyo

The Graduate University for Advanced Studies (SOKENDAI)

National Astronomical Observatory of Japan

Chih-Wei L. Huang

Academia Sinica

Lei Huang

Chinese Academy of Sciences

David H. Hughes

National Institute of Astrophysics, Optics and Electronics

Shiro Ikeda

University of Tokyo

The Institute of Statistical Mathematics

The Graduate University for Advanced Studies (SOKENDAI)

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

Saint Petersburg State University - Spsu

Boston University

Taehyun Jung

University of Science and Technology (UST)

Korea Astronomy and Space Science Institute

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

California Institute of Technology (Caltech)

University of Arizona

Motoki Kino

National Astronomical Observatory of Japan

Kogakuin University of Technology and Engineering

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

National Sun Yat-Sen University

Academia Sinica

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

Spanish National Research Council (CSIC)

Max Planck Society

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

National Taiwan University

Academia Sinica

Andrei P. Lobanov

Max Planck Society

Laurent Loinard

Universidad Nacional Autónoma de México

Colin Lonsdale

Massachusetts Institute of Technology (MIT)

Ru-Sen Lu

Max Planck Society

Chinese Academy of Sciences

Nicholas R. MacDonald

Max Planck Society

Jirong Mao

Chinese Academy of Sciences

Nicola Marchili

Istituto nazionale di astrofisica (INAF)

Max Planck Society

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-Smithsonian Center for Astrophysics

Harvard University

Kotaro Moriyama

Massachusetts Institute of Technology (MIT)

National Astronomical Observatory of Japan

Monika Moscibrodzka

Radboud University

Cornelia Muller

Max Planck Society

Radboud University

Gibwa Musoke

Radboud University

University of Amsterdam

Alejandro Mus Mejias

Universitat de Valencia

Daniel Michalik

University of Chicago

European Space Research and Technology Centre (ESA ESTEC)

Andrew Nadolski

University of Illinois

Hiroshi Nagai

The Graduate University for Advanced Studies (SOKENDAI)

National Astronomical Observatory of Japan

Neil M. Nagar

University of Concepcion

Masanori Nakamura

Academia Sinica

National Institute of Technology, Hachinohe College

Ramesh Narayan

Harvard-Smithsonian Center for Astrophysics

Harvard University

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

Joey 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

National Astronomical Observatory of Japan

University of Tokyo

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 University

Harvard-Smithsonian Center for Astrophysics

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 University

Harvard-Smithsonian Center for Astrophysics

Vincent Pietu

Institut de Radioastronomie Millimétrique (IRAM)

Richard Plambeck

University of California at Berkeley

Aleksandar PopStefanija

University of Massachusetts

Oliver Porth

Goethe University Frankfurt

University of Amsterdam

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

Perimeter Institute for Theoretical Physics

Academia Sinica

National Taiwan Normal University

Venkatessh Ramakrishnan

University of Concepcion

Ramprasad Rao

Academia Sinica

Mark G. Rawlings

East Asian Observatory

Alexander W. Raymond

Harvard University

Harvard-Smithsonian Center for Astrophysics

Luciano Rezzolla

Trinity College Dublin

Frankfurt Institute for Advanced Studies

Goethe University Frankfurt

Angelo Ricarte

Harvard-Smithsonian Center for Astrophysics

Harvard University

Bart Ripperda

Flatiron Institute

Princeton University

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

University of Science and Technology (UST)

Korea Astronomy and Space Science Institute

Yonsei University

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)

University of Arizona

Radboud University

Leiden University

Michael Titus

Massachusetts Institute of Technology (MIT)

Kenji Toma

Tohoku University

Pablo Torne

Institut de Radioastronomie Millimétrique (IRAM)

Max Planck Society

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

Leiden University

Joint Institute for VLBI in Europe (JIVE)

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 University

Harvard-Smithsonian Center for Astrophysics

Norbert Wex

Max Planck Society

Robert Wharton

Max Planck Society

Maciek Wielgus

Harvard University

Harvard-Smithsonian Center for Astrophysics

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 L12

Subject Categories

Astronomy, Astrophysics and Cosmology

Computer Vision and Robotics (Autonomous Systems)

Medical Image Processing

DOI

10.3847/2041-8213/abe71d

More information

Latest update

6/13/2022