Polarimetric Properties of Event Horizon Telescope Targets from ALMA
Journal article, 2021

We present the results from a full polarization study carried out with the Atacama Large Millimeter/submillimeter Array (ALMA) during the first Very Long Baseline Interferometry (VLBI) campaign, which was conducted in 2017 April in the lambda 3 mm and lambda 1.3 mm bands, in concert with the Global mm-VLBI Array (GMVA) and the Event Horizon Telescope (EHT), respectively. We determine the polarization and Faraday properties of all VLBI targets, including Sgr A*, M87, and a dozen radio-loud active galactic nuclei (AGNs), in the two bands at several epochs in a time window of 10 days. We detect high linear polarization fractions (2%-15%) and large rotation measures (RM > 10(3.3)-10(5.5) rad m(-2)), confirming the trends of previous AGN studies at millimeter wavelengths. We find that blazars are more strongly polarized than other AGNs in the sample, while exhibiting (on average) order-of-magnitude lower RM values, consistent with the AGN viewing angle unification scheme. For Sgr A* we report a mean RM of (-4.2 0.3) x 10(5) rad m(-2) at 1.3 mm, consistent with measurements over the past decade and, for the first time, an RM of (-2.1 0.1) x 10(5) rad m(-2) at 3 mm, suggesting that about half of the Faraday rotation at 1.3 mm may occur between the 3 mm photosphere and the 1.3 mm source. We also report the first unambiguous measurement of RM toward the M87 nucleus at millimeter wavelengths, which undergoes significant changes in magnitude and sign reversals on a one year timescale, spanning the range from -1.2 to 0.3 x 10(5) rad m(-2) at 3 mm and -4.1 to 1.5 x 10(5) rad m(-2) at 1.3 mm. Given this time variability, we argue that, unlike the case of Sgr A*, the RM in M87 does not provide an accurate estimate of the mass accretion rate onto the black hole. We put forward a two-component model, comprised of a variable compact region and a static extended region, that can simultaneously explain the polarimetric properties observed by both the EHT (on horizon scales) and ALMA (which observes the combined emission from both components). These measurements provide critical constraints for the calibration, analysis, and interpretation of simultaneously obtained VLBI data with the EHT and GMVA.

Magnetic fields

Relativistic jets

Blazars

Long baseline interferometry

Galactic center

Interferometry

Polarimetry

Supermassive black holes

Quasars

Active galactic nuclei

Radio galaxies

Radio jets

Author

Ciriaco Goddi

Radboud University

Leiden University

Ivan Marti-Vidal

Universitat de Valencia

Hugo Messias

Atacama Large Millimeter-submillimeter Array (ALMA)

Geoffrey C. Bower

Academia Sinica

Avery E. Broderick

Perimeter Institute for Theoretical Physics

University of Waterloo

Jason Dexter

University of Colorado

Daniel P. Marrone

University of Arizona

Monika Moscibrodzka

Radboud University

Hiroshi Nagai

The Graduate University for Advanced Studies (SOKENDAI)

National Astronomical Observatory of Japan

Juan Carlos Algaba

University of Malaya

Keiichi Asada

Academia Sinica

Geoffrey B. Crew

Massachusetts Institute of Technology (MIT)

Jose L. Gomez

Spanish National Research Council (CSIC)

C. M. Violette Impellizzeri

Atacama Large Millimeter-submillimeter Array (ALMA)

Leiden University

Michael Janssen

Max Planck Society

Matthias Kadler

University of Würzburg

Thomas P. Krichbaum

Max Planck Society

Rocco Lico

Max Planck Society

Spanish National Research Council (CSIC)

Lynn D. Matthews

Massachusetts Institute of Technology (MIT)

Antonios Nathanail

National and Kapodistrian University of Athens

Goethe University Frankfurt

Angelo Ricarte

Harvard-Smithsonian Center for Astrophysics

Harvard University

Eduardo Ros

Max Planck Society

Ziri Younsi

University College London (UCL)

Goethe University Frankfurt

Kazunori Akiyama

National Astronomical Observatory of Japan

National Radio Astronomy Observatory

Massachusetts Institute of Technology (MIT)

Harvard University

Antxon Alberdi

Spanish National Research Council (CSIC)

Walter Alef

Max Planck Society

Richard Anantua

Flatiron Institute

Harvard University

Harvard-Smithsonian Center for Astrophysics

Rebecca Azulay

Max Planck Society

Universitat de Valencia

Anne-Kathrin Baczko

Max Planck Society

David Ball

University of Arizona

Mislay Balokovic

Yale Ctr Astron & Astrophys, 52 Hillhouse Ave

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

NOVA

Katherine L. Bouman

Harvard-Smithsonian Center for Astrophysics

California Institute of Technology (Caltech)

Harvard University

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

Dominique Broguiere

Institut de Radioastronomie Millimétrique (IRAM)

Thomas Bronzwaer

Radboud University

Do-Young Byun

Korea Astronomy and Space Science Institute

University of Science and Technology (UST)

John E. Carlstrom

University of Chicago

Andrew Chael

ESO FINCA

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

Alejandro Cruz-Osorio

Goethe University Frankfurt

Yuzhu Cui

National Astronomical Observatory of Japan

The Graduate University for Advanced Studies (SOKENDAI)

Jordy Davelaar

Flatiron Institute

Columbia University

Radboud 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

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

University of Massachusetts

Harvard-Smithsonian Center for Astrophysics

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

Goethe University Frankfurt

Harvard-Smithsonian Center for Astrophysics

Harvard University

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

Roman Gold

University of Southern Denmark

Perimeter Institute for Theoretical Physics

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

University of Tokyo

National Astronomical Observatory of Japan

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

Makoto Inoue

Academia Sinica

Sara Issaoun

Radboud University

David J. James

Harvard-Smithsonian Center for Astrophysics

Harvard University

Buell T. Jannuzi

University of Arizona

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

University of Arizona

California Institute of Technology (Caltech)

Motoki Kino

National Astronomical Observatory of Japan

Kogakuin University of Technology and Engineering

Jun Yi Koay

Academia Sinica

Yutaro Kofuji

National Astronomical Observatory of Japan

University of Tokyo

Patrick M. Koch

Academia Sinica

Shoko Koyama

Academia Sinica

Michael Kramer

Max Planck Society

Carsten Kramer

Institut de Radioastronomie Millimétrique (IRAM)

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

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

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

Alan P. Marscher

Boston University

Satoki Matsushita

Academia Sinica

Lia Medeiros

Institute for Advanced Study

University of Arizona

Karl M. Menten

Max Planck Society

Izumi Mizuno

East Asian Observatory

Yosuke Mizuno

Shanghai Jiao Tong University

Goethe University Frankfurt

James M. Moran

Harvard University

Harvard-Smithsonian Center for Astrophysics

Kotaro Moriyama

National Astronomical Observatory of Japan

Massachusetts Institute of Technology (MIT)

Cornelia Muller

Radboud University

Max Planck Society

Gibwa Musoke

University of Amsterdam

Radboud University

Alejandro Mus Mejias

Universitat de Valencia

Neil M. Nagar

University of Concepcion

Masanori Nakamura

National Institute of Technology (KOSEN)

Academia Sinica

Ramesh Narayan

Harvard University

Harvard-Smithsonian Center for Astrophysics

Gopal Narayanan

University of Massachusetts

Iniyan Natarajan

Rhodes University

South African Radio Astronomy Observatory (SARAO)

University of Witwatersrand

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 University

Harvard-Smithsonian Center for Astrophysics

Jongho Park

Academia Sinica

Nimesh Patel

Harvard-Smithsonian Center for Astrophysics

Ue-Li Pen

Perimeter Institute for Theoretical Physics

University of Toronto

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

Aleksandar PopStefanija

University of Massachusetts

Oliver Porth

Goethe University Frankfurt

University of Amsterdam

Felix M. Poetzl

Max Planck Society

Ben Prather

University of Illinois

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-Smithsonian Center for Astrophysics

Harvard University

Luciano Rezzolla

Frankfurt Institute for Advanced Studies

Trinity College Dublin

Inst Theoret Phys

Bart Ripperda

Princeton University

Flatiron Institute

Freek Roelofs

Radboud University

Alan Rogers

Massachusetts Institute of Technology (MIT)

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

Hiroshima University

National Astronomical Observatory of Japan

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

Radboud University

University of Arizona

East Asian Observatory

Leiden University

Michael Titus

Massachusetts Institute of Technology (MIT)

Kenji Toma

Netherlands Organisation for Scientific Research (NWO)

Tohoku University

Pablo Torne

Institut de Radioastronomie Millimétrique (IRAM)

Max Planck Society

Tyler Trent

University of Arizona

Efthalia Traianou

Max Planck Society

Sascha Trippe

Tohoku University

Ilse van Bemmel

Joint Institute for VLBI in Europe (JIVE)

Huib Jan van Langevelde

Seoul National University

Joint Institute for VLBI in Europe (JIVE)

Daniel R. van Rossum

Radboud University

Jan Wagner

Max Planck Society

Derek Ward-Thompson

Leiden University

John Wardle

University of Central Lancashire

Jonathan Weintroub

Harvard University

Harvard-Smithsonian Center for Astrophysics

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

Brandeis University

Feng Yuan

Huazhong University of Science and Technology

Chinese Academy of Sciences

Doosoo Yoon

University of Amsterdam

Andre Young

Radboud University

Ken Young

Harvard-Smithsonian Center for Astrophysics

Ye-Fei Yuan

Chinese Academy of Sciences

J. Anton Zensus

Max Planck Society

Guang-Yao Zhao

Spanish National Research Council (CSIC)

Shan-Shan Zhao

Chinese Academy of Sciences

Gabriele Bruni

University of Science and Technology of China

A. Gopakumar

Istituto nazionale di astrofisica (INAF)

Antonio Hernandez-Gomez

Max Planck Society

Ruben Herrero-Illana

Spanish National Research Council (CSIC)

Tata Institute of Fundamental Research

Adam Ingram

European Southern Observatory (ESO)

S. Komossa

Max Planck Society

Y. Y. Kovalev

Russian Academy of Sciences

Max Planck Society

University of Oxford

Dirk Muders

Max Planck Society

Manel Perucho

Universitat de Valencia

Florian Rosch

University of Würzburg

Mauri Valtonen

Moscow Institute of Physics and Technology

Astrophysical Journal Letters

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

Vol. 910 1 L14

Subject Categories (SSIF 2011)

Meteorology and Atmospheric Sciences

Astronomy, Astrophysics and Cosmology

Environmental Sciences

Infrastructure

Onsala Space Observatory

DOI

10.3847/2041-8213/abee6a

More information

Latest update

7/3/2025 1