First Sagittarius A∗ Event Horizon Telescope Results. VII. Polarization of the Ring
Journal article, 2024

The Event Horizon Telescope observed the horizon-scale synchrotron emission region around the Galactic center supermassive black hole, Sagittarius A∗ (Sgr A∗), in 2017. These observations revealed a bright, thick ring morphology with a diameter of 51.8 ± 2.3 μas and modest azimuthal brightness asymmetry, consistent with the expected appearance of a black hole with mass M≈ 4 × 106 M⊙. From these observations, we present the first resolved linear and circular polarimetric images of Sgr A∗. The linear polarization images demonstrate that the emission ring is highly polarized, exhibiting a prominent spiral electric vector polarization angle pattern with a peak fractional polarization of ∼40% in the western portion of the ring. The circular polarization images feature a modestly (∼5%°-10%) polarized dipole structure along the emission ring, with negative circular polarization in the western region and positive circular polarization in the eastern region, although our methods exhibit stronger disagreement than for linear polarization. We analyze the data using multiple independent imaging and modeling methods, each of which is validated using a standardized suite of synthetic data sets. While the detailed spatial distribution of the linear polarization along the ring remains uncertain owing to the intrinsic variability of the source, the spiraling polarization structure is robust to methodological choices. The degree and orientation of the linear polarization provide stringent constraints for the black hole and its surrounding magnetic fields, which we discuss in an accompanying publication.

Author

Kazunori Akiyama

Massachusetts Institute of Technology (MIT)

Antxon Alberdi

Institute of Astrophysics of Andalusia (IAA)

Walter Alef

Max Planck Society

Juan-Carlos Algaba

University of Malaya

Richard Anantua

Harvard University

Richard Anantua

Academia Sinica

R. Azulay

Max Planck Society

U. Bach

Max Planck Society

A. K. Baczko

Max Planck Society

David Ball

University of Arizona

Mislav Baloković

Yale University

Bidisha Bandyopadhyay

University of Concepcion

John Barrett

Massachusetts Institute of Technology (MIT)

M. Bauböck

University of Illinois

Bradford A. Benson

Fermi National Accelerator Laboratory

Dan Bintley

East Asian Observatory

Lindy Blackburn

Harvard University

R. Blundell

Harvard-Smithsonian Center for Astrophysics

K. L. Bouman

California Institute of Technology (Caltech)

G. C. Bower

Academia Sinica

Hope Boyce

McGill University

Michael Bremer

Institut de Radioastronomie Millimétrique (IRAM)

C. D. Brinkerink

Radboud University

Roger Brissenden

Harvard University

Silke Britzen

Max Planck Society

Avery E. Broderick

Perimeter Institute for Theoretical Physics

D. Broguière

Institut de Radioastronomie Millimétrique (IRAM)

Thomas Bronzwaer

Radboud University

Sandra Bustamente

University of Massachusetts

Do-Young Byun

Korea Astronomy and Space Science Institute

J. E. Carlstrom

University of Chicago

Chiara Ceccobello

Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics

A. Chael

Princeton University

Chi Kwan Chan

University of Arizona

Dominic O. Chang

Harvard University

Chiara Ceccobello

Harvard University

S. Chatterjee

Cornell University

Ming Tang Chen

Academia Sinica

Yongjun Chen

Shanghai Astronomical Observatory

X. P. Cheng

Korea Astronomy and Space Science Institute

I. Cho

Institute of Astrophysics of Andalusia (IAA)

Pierre Christian

Fairfield University

Nicholas S. Conroy

Harvard-Smithsonian Center for Astrophysics

John Conway

Chalmers, Space, Earth and Environment, Onsala Space Observatory

James M. Cordes

Cornell University

Thomas M. Crawford

University of Chicago

G. Crew

Massachusetts Institute of Technology (MIT)

Alejandro Cruz-Osorio

Universidad Nacional Autónoma de México

Yuzhu Cui

Zhejiang Lab

Rohan Dahale

Institute of Astrophysics of Andalusia (IAA)

Jordy Davelaar

Radboud University

Mariafelicia De Laurentis

Goethe University Frankfurt

R. P. Deane

University of Witwatersrand

Rohan Dahale

East Asian Observatory

Gregory Desvignes

Max Planck Society

Jason Dexter

JILA

Vedant Dhruv

University of Illinois

Indu K. Dihingia

Shanghai Jiao Tong University

S. Doeleman

Harvard University

Sean Dougal

University of Arizona

Sergio A. Dzib

Max Planck Society

Ralph P. Eatough

Max Planck Society

Razieh Emami

Harvard-Smithsonian Center for Astrophysics

H.D. Falcke

Radboud University

Joseph R. Farah

Las Cumbres Observatory Global Telescope Network

V. Fish

Massachusetts Institute of Technology (MIT)

E. Fomalont

National Radio Astronomy Observatory

H. Alyson Ford

University of Arizona

Marianna Foschi

Institute of Astrophysics of Andalusia (IAA)

R. Fraga-Encinas

Radboud University

William T. Freeman

Massachusetts Institute of Technology

E. Fomalont

East Asian Observatory

Christian M. Fromm

Max Planck Society

Antonio Fuentes

Institute of Astrophysics of Andalusia (IAA)

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 Arizona

C. Goddi

University of Sao Paulo (USP)

R. Gold

University of Southern Denmark

Arturo I. Gómez-Ruiz

National Institute of Astrophysics, Optics and Electronics

José L. Gómez

Institute of Astrophysics of Andalusia (IAA)

Minfeng Gu

Shanghai Astronomical Observatory

M. Gurwell

Harvard-Smithsonian Center for Astrophysics

K. Hada

National Astronomical Observatory of Japan

Daryl Haggard

McGill University

Kari Haworth

Harvard-Smithsonian Center for Astrophysics

Michael H. Hecht

Massachusetts Institute of Technology (MIT)

R. Hesper

University of Groningen

Dirk Heumann

University of Arizona

Luis C. Ho

Beijing University of Technology

P. T. P. Ho

Academia Sinica

Mareki Honma

National Astronomical Observatory of Japan

Chih Wei L. Huang

Academia Sinica

Lei Huang

Shanghai Astronomical Observatory

David H. Hughes

National Institute of Astrophysics, Optics and Electronics

Shiro Ikeda

National Astronomical Observatory of Japan

C.M. Violette Impellizzeri

National Radio Astronomy Observatory

Makoto Inoue

Academia Sinica

S. Issaoun

Harvard-Smithsonian Center for Astrophysics

David J. James

ASTRAVEO

Buell T. Jannuzi

University of Arizona

Lei Huang

Max Planck Society

Britton Jeter

Academia Sinica

Wu Jiang

Shanghai Astronomical Observatory

Alejandra Jimenez-Rosales

Radboud University

Makoto Inoue

Harvard University

S.G. Jorstad

Boston University

Abhishek V. Joshi

University of Illinois

Taehyun Jung

Korea Astronomy and Space Science Institute

Mansour Karami

Perimeter Institute for Theoretical Physics

R. Karuppusamy

Max Planck Society

Tomohisa Kawashima

University of Tokyo

G. Keating

Harvard-Smithsonian Center for Astrophysics

M. M. Kettenis

Joint Institute for VLBI in Europe (JIVE)

Dong-Jin Kim

Max Planck Society

Jae-Young Kim

Max Planck Society

Jongsoo Kim

Korea Astronomy and Space Science Institute

Junhan Kim

Korea Advanced Institute of Science and Technology (KAIST)

R. Karuppusamy

National Astronomical Observatory of Japan

Jun Yi Koay

Academia Sinica

Prashant Kocherlakota

Goethe University Frankfurt

Yutaro Kofuji

National Astronomical Observatory of Japan

M. M. Kettenis

Academia Sinica

Shoko Koyama

Academia Sinica

Jae-Young Kim

Institut de Radioastronomie Millimétrique (IRAM)

Joana A. Kramer

Max Planck Society

M. Kramer

Max Planck Society

T.P. Krichbaum

Max Planck Society

Greg Lindahl

Academia Sinica

Michael Lindqvist

Radboud University

Tod R. Lauer

National Optical Astronomy Observatory

Daeyoung Lee

University of Illinois

Sang Sung Lee

Korea Astronomy and Space Science Institute

Po Kin Leung

Chinese University of Hong Kong

Aviad Levis

California Institute of Technology (Caltech)

Zhiyuan Li

Nanjing University

R. Lico

Institute of Astrophysics of Andalusia (IAA)

Greg Lindahl

Harvard-Smithsonian Center for Astrophysics

Michael Lindqvist

Chalmers, Space, Earth and Environment, Onsala Space Observatory

Mikhail Lisakov

Max Planck Society

Jun Liu

Max Planck Society

Kuo Liu

Max Planck Society

Elisabetta Liuzzo

Istituto nazionale di astrofisica (INAF)

Wen-Ping Lo

Academia Sinica

A. P. Lobanov

Max Planck Society

L. Loinard

Universidad Nacional Autónoma de México

Greg Lindahl

Massachusetts Institute of Technology (MIT)

Amy E. Lowitz

University of Arizona

R.S. Lu

Max Planck Society

N. R. Macdonald

Max Planck Society

Jirong Mao

Yunnan Observatories

Nicola Marchili

Max Planck Society

S. Markoff

Anton Pannekoek Institute for Astronomy

D. P. Marrone

University of Arizona

A. Marscher

Boston University

Ivan Marti-Vidal

Universitat de Valencia

Amy E. Lowitz

Academia Sinica

Lynn D. Matthews

Massachusetts Institute of Technology (MIT)

Lia Medeiros

NASA Hubble Fellowship Program

K. Menten

Max Planck Society

Daniel Michalik

University of Chicago

Izumi Mizuno

East Asian Observatory

Yosuke Mizuno

Goethe University Frankfurt

James M. Moran

Harvard University

Kotaro Moriyama

Massachusetts Institute of Technology (MIT)

M. Mościbrodzka

Radboud University

Wanga Mulaudzi

Anton Pannekoek Institute for Astronomy

C. Müller

Max Planck Society

Hendrik Müller

Max Planck Society

A. Mus

Universitat de Valencia

Gibwa Musoke

Radboud University

I. Myserlis

Institut de Radioastronomie Millimétrique (IRAM)

Andrew Nadolski

University of Illinois

H. Nagai

National Astronomical Observatory of Japan

N. M. Nagar

University of Concepcion

Lia Medeiros

Academia Sinica

Daniel Michalik

University of Massachusetts

Iniyan Natarajan

Harvard University

Antonios Nathanail

Goethe University Frankfurt

Santiago Navarro Fuentes

Institut de Radioastronomie Millimétrique (IRAM)

Joseph Neilsen

Villanova University

R. Neri

Institut de Radioastronomie Millimétrique (IRAM)

Chunchong Ni

Perimeter Institute for Theoretical Physics

A. Noutsos

Max Planck Society

M.A. Nowak

Washington University in St. Louis

Junghwan Oh

Joint Institute for VLBI in Europe (JIVE)

Hiroki Okino

National Astronomical Observatory of Japan

Héctor Olivares

Radboud University

G.N. Ortiz-León

Max Planck Society

Tomoaki Oyama

National Astronomical Observatory of Japan

Feryal Özel

Georgia Institute of Technology

N. Patel

Harvard University

Georgios Filippos Paraschos

Max Planck Society

Jongho Park

Kyung Hee University

Harriet Parsons

East Asian Observatory

N. Patel

Harvard-Smithsonian Center for Astrophysics

U. L. Pen

Academia Sinica

Dominic W. Pesce

Harvard University

Vincent Piétu

Institut de Radioastronomie Millimétrique (IRAM)

Richard L. Plambeck

University of California

Aleksandar PopStefanija

University of Massachusetts

Oliver Porth

Goethe University Frankfurt

Felix M. Pötzl

Max Planck Society

Ben Prather

University of Illinois

Jorge A. Preciado-López

Perimeter Institute for Theoretical Physics

Dimitrios Psaltis

Georgia Institute of Technology

Hung-Yi Pu

Academia Sinica

Venkatessh Ramakrishnan

University of Concepcion

R. Rao

Harvard-Smithsonian Center for Astrophysics

M.G. Rawlings

East Asian Observatory

Alexander W. Raymond

Harvard University

Luciano Rezzolla

Goethe University Frankfurt

Angelo Ricarte

Harvard University

Bart Ripperda

Perimeter Institute for Theoretical Physics

F. Roelofs

Harvard University

A.E.E. Rogers

Massachusetts Institute of Technology (MIT)

C. Romero-Cañizales

Academia Sinica

Eduardo Ros

Max Planck Society

Arash Roshanineshat

University of Arizona

H. Rottmann

Max Planck Society

A. Roy

Max Planck Society

Ignacio Ruiz

Institut de Radioastronomie Millimétrique (IRAM)

C. Ruszczyk

Massachusetts Institute of Technology (MIT)

Kazi L.J. Rygl

Istituto nazionale di astrofisica (INAF)

S. Sanchez

Institut de Radioastronomie Millimétrique (IRAM)

David Sánchez-Arguelles

National Institute of Astrophysics, Optics and Electronics

M. Sánchez Portal

Institut de Radioastronomie Millimétrique (IRAM)

Mahito Sasada

National Astronomical Observatory of Japan

Kaushik Satapathy

University of Arizona

T. Savolainen

Max Planck Society

F. P. Schloerb

University of Massachusetts

Jonathan Schonfeld

Harvard-Smithsonian Center for Astrophysics

K. Schuster

Institut de Radioastronomie Millimétrique (IRAM)

Lijing Shao

Max Planck Society

Zhi Qiang Shen

Shanghai Astronomical Observatory

Des Small

Joint Institute for VLBI in Europe (JIVE)

Bong Won Sohn

Korea Astronomy and Space Science Institute

J. SooHoo

Massachusetts Institute of Technology (MIT)

León David Sosapanta Salas

Anton Pannekoek Institute for Astronomy

Kamal Souccar

University of Massachusetts

Joshua S. Stanway

University of Central Lancashire

He Sun

Beijing University of Technology

Fumie Tazaki

National Astronomical Observatory of Japan

Alexandra J. Tetarenko

University of Lethbridge

Paul Tiede

Harvard University

R. P. J. Tilanus

University of Arizona

M. Titus

Massachusetts Institute of Technology (MIT)

Pablo Torne

Max Planck Society

Teresa Toscano

Institute of Astrophysics of Andalusia (IAA)

E. Traianou

Institute of Astrophysics of Andalusia (IAA)

Tyler Trent

University of Arizona

S. Trippe

Seoul National University

Matthew Turk

University of Illinois

I. van Bemmel

Joint Institute for VLBI in Europe (JIVE)

H. J. van Langevelde

Leiden University

Daniel R. van Rossum

Radboud University

Jesse Vos

Radboud University

Jan Wagner

Max Planck Society

D. Ward-Thompson

University of Central Lancashire

John Wardle

Brandeis University

Jasmin E. Washington

University of Arizona

J. Weintroub

Harvard University

Robert Wharton

Max Planck Society

M. Wielgus

Max Planck Society

K. Wiik

Tuorla Observatory

Gunther Witzel

Max Planck Society

Michael F. Wondrak

Radboud University

George N. Wong

Princeton University

Qingwen Wu

Huazhong University of Science and Technology

Nitika Yadlapalli

California Institute of Technology (Caltech)

Paul Yamaguchi

Harvard-Smithsonian Center for Astrophysics

Aristomenis Yfantis

Radboud University

Doosoo Yoon

Anton Pannekoek Institute for Astronomy

A. Young

Radboud University

Ken Young

Harvard-Smithsonian Center for Astrophysics

Ziri Younsi

Goethe University Frankfurt

Wei Yu

Harvard-Smithsonian Center for Astrophysics

Feng Yuan

Fudan University

Ye-Fei Yuan

University of Science and Technology of China

A. Zensus

Max Planck Society

Shuo Zhang

Michigan State University

G. Y. Zhao

Institute of Astrophysics of Andalusia (IAA)

Shan-Shan Zhao

Shanghai Astronomical Observatory

Astrophysical Journal Letters

2041-8205 (ISSN) 2041-8213 (eISSN)

Vol. 964 2 L25

Subject Categories

Astronomy, Astrophysics and Cosmology

Computer Vision and Robotics (Autonomous Systems)

DOI

10.3847/2041-8213/ad2df0

More information

Latest update

4/19/2024