First polarization study of the M87 jet and active galactic nuclei at submillimeter wavelengths with ALMA
Artikel i vetenskaplig tidskrift, 2025

Aims. We investigated the polarization and Faraday properties of Messier 87 (M87) and seven other radio-loud active galactic nuclei (AGNs) at _0.87mm (345 GHz) using the Atacama Large Millimeter/submillimeter Array (ALMA). Our goal was to characterize the linear polarization (LP) fractions, measure Faraday rotation measures (RMs), and examine the magnetic field structures in the emission regions of these AGNs. Methods. We conducted full-polarization observations as part of the ALMA Band 7 very long baseline interferometry (VLBI) commissioning during the April 2021 Event Horizon Telescope (EHT) campaign. We analyzed the LP fractions and RMs to assess the nature of Faraday screens and magnetic fields in the submillimeter emission regions. Results. We find LP fractions between 1% and 17% and RMs exceeding 105 radm-2, which are 1-2 orders of magnitude higher than typically observed at longer wavelengths (λ > 3 mm). This suggests denser Faraday screens or stronger magnetic fields. Additionally, we present the first submillimeter polarized images of the M87 jet and the observed AGNs, revealing RM gradients and sign reversals in the M87 jet indicative of a kiloparsec-scale helical magnetic field structure. Conclusions. Our results provide essential constraints for calibrating, analyzing, and interpreting VLBI data from the EHT at 345 GHz, representing a critical step toward submillimeter VLBI imaging.

Black hole physics

Polarization

Instrumentation: interferometers

Radiation mechanisms: non-thermal

Magnetic fields

Instrumentation: polarimeters

Författare

C. Goddi

Istituto nazionale di astrofisica (INAF)

Universita degli Studi di Cagliari

Universidade de Sao Paulo (USP)

Douglas Ferreira Carlos

Universidade de Sao Paulo (USP)

G. Crew

Massachusetts Institute of Technology (MIT)

Lynn D. Matthews

Massachusetts Institute of Technology (MIT)

H. Messias

Atacama Large Millimeter-submillimeter Array (ALMA)

A. Mus

Istituto di Radioastronomia

Universita degli Studi di Cagliari

Ivan Marti-Vidal

Universitat de Valencia

E. Albentosa-Ruiz

Universitat de Valencia

Mariafelicia De Laurentis

Istituto Nazionale di Fisica Nucleare

Universita degli Studi di Napoli Federico II

Elisabetta Liuzzo

Istituto di Radioastronomia

Nicola Marchili

Max-Planck-Gesellschaft

Istituto di Radioastronomia

Kazi L.J. Rygl

Istituto di Radioastronomia

Kazunori Akiyama

Massachusetts Institute of Technology (MIT)

Harvard University

National Astronomical Observatory of Japan

Antxon Alberdi

Consejo Superior de Investigaciones Científicas (CSIC)

Walter Alef

Max-Planck-Gesellschaft

Juan Carlos Algaba

University of Malaya

Richard Anantua

Rice University

University of Texas

Harvard-Smithsonian Center for Astrophysics

Harvard University

K. Asada

Academia Sinica

R. Azulay

Universitat de Valencia

Max-Planck-Gesellschaft

U. Bach

Max-Planck-Gesellschaft

Anne-Kathrin Baczko

Max-Planck-Gesellschaft

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik

David Ball

University of Arizona

Mislav Balokoviä

Yale University

Bidisha Bandyopadhyay

Universidad de Concepción

John Barrett

Massachusetts Institute of Technology (MIT)

M. Bauböck

Grainger College of Engineering

Bradford A. Benson

University of Chicago

Fermi National Accelerator Laboratory

Dan Bintley

East Asian Observatory

James Clerk Maxwell Telescope

Lindy Blackburn

Harvard University

Harvard-Smithsonian Center for Astrophysics

R. Blundell

Harvard-Smithsonian Center for Astrophysics

K. L. Bouman

California Institute of Technology (Caltech)

G. C. Bower

Academia Sinica

University of Hawaii

M. Bremer

Institut de Radioastronomie Millimétrique (IRAM)

Roger Brissenden

Harvard University

Harvard-Smithsonian Center for Astrophysics

Silke Britzen

Max-Planck-Gesellschaft

Avery E. Broderick

University of Waterloo

Perimeter Institute for Theoretical Physics

D. Broguière

Institut de Radioastronomie Millimétrique (IRAM)

Thomas Bronzwaer

Radboud Universiteit

Sandra Bustamente

University of Massachusetts

J. E. Carlstrom

University of Chicago

The Enrico Fermi Institute

A. Chael

Princeton University

Chi Kwan Chan

University of Arizona

Dominic O. Chang

Harvard University

Harvard-Smithsonian Center for Astrophysics

Koushik Chatterjee

Harvard University

Harvard-Smithsonian Center for Astrophysics

S. Chatterjee

Cornell University

Ming Tang Chen

Academia Sinica

Yongjun Chen

Chinese Academy of Sciences

X. P. Cheng

Korea Astronomy and Space Science Institute

I. Cho

Consejo Superior de Investigaciones Científicas (CSIC)

Yonsei University

Korea Astronomy and Space Science Institute

Pierre Christian

WattTime

Nicholas S. Conroy

University of Illinois

Harvard-Smithsonian Center for Astrophysics

John Conway

Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium

Thomas M. Crawford

University of Chicago

Alejandro Cruz-Osorio

Johann Wolfgang Goethe Universität Frankfurt am Main

Universidad Nacional Autónoma de México

Yuzhu Cui

Shanghai Jiao Tong University

Zhejiang Lab

Brandon Curd

University of Texas

Harvard University

Harvard-Smithsonian Center for Astrophysics

Rohan Dahale

Consejo Superior de Investigaciones Científicas (CSIC)

Jordy Davelaar

Princeton University

R. P. Deane

Universiteit van Pretoria

Rhodes University

University of Witwatersrand

Jessica Dempsey

Netherlands Institute for Radio Astronomy (ASTRON)

East Asian Observatory

James Clerk Maxwell Telescope

Gregory Desvignes

Max-Planck-Gesellschaft

Observatoire de Paris

Jason Dexter

JILA

Vedant Dhruv

Grainger College of Engineering

Indu K. Dihingia

Shanghai Jiao Tong University

S. Doeleman

Harvard-Smithsonian Center for Astrophysics

Harvard University

Sergio A. Dzib

Max-Planck-Gesellschaft

Ralph P. Eatough

Max-Planck-Gesellschaft

Chinese Academy of Sciences

Razieh Emami

Harvard-Smithsonian Center for Astrophysics

H.D. Falcke

Radboud Universiteit

Joseph R. Farah

Las Cumbres Observatory Global Telescope Network

University of California

V. Fish

Massachusetts Institute of Technology (MIT)

E. Fomalont

National Radio Astronomy Observatory

Marianna Foschi

Consejo Superior de Investigaciones Científicas (CSIC)

R. Fraga-Encinas

Radboud Universiteit

William T. Freeman

Google Inc.

Massachusetts Institute of Technology (MIT)

P. Friberg

James Clerk Maxwell Telescope

East Asian Observatory

Christian M. Fromm

Julius-Maximilians Universität Würzburg

Max-Planck-Gesellschaft

Johann Wolfgang Goethe Universität Frankfurt am Main

Antonio Fuentes

Consejo Superior de Investigaciones Científicas (CSIC)

Peter Galison

Harvard University

Charles F. Gammie

Grainger College of Engineering

University of Illinois

Roberto Garcia

Institut de Radioastronomie Millimétrique (IRAM)

Olivier Gentaz

Institut de Radioastronomie Millimétrique (IRAM)

Boris Georgiev

University of Arizona

R. Gold

Universität Heidelberg

Syddansk Universitet

Arturo I. Gómez-Ruiz

Instituto Nacional de Astrofísica, Óptica y Electrońica

Consejo Nacional de Ciencia y Tecnologia Mexico

J. L. Gomez

Consejo Superior de Investigaciones Científicas (CSIC)

Minfeng Gu

Chinese Academy of Sciences

M. Gurwell

Harvard-Smithsonian Center for Astrophysics

K. Hada

National Astronomical Observatory of Japan

University of Tokyo

Daryl Haggard

McGill University

R. Hesper

Rijksuniversiteit Groningen

Dirk Heumann

University of Arizona

Luis C. Ho

Beijing University of Technology

P. T. P. Ho

Academia Sinica

James Clerk Maxwell Telescope

East Asian Observatory

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

D. Hughes

Instituto Nacional de Astrofísica, Óptica y Electrońica

Shiro Ikeda

National Astronomical Observatory of Japan

The Graduate University for Advanced Studies (SOKENDAI)

University of Tokyo

The Institute of Statistical Mathematics

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 699 A265

Ämneskategorier (SSIF 2025)

Atom- och molekylfysik och optik

Astronomi, astrofysik och kosmologi

Meteorologi och atmosfärsvetenskap

DOI

10.1051/0004-6361/202554140

Mer information

Senast uppdaterat

2026-07-03