First M87 Event Horizon Telescope Results. II. Array and Instrumentation
Journal article, 2019

The Event Horizon Telescope (EHT) is a very long baseline interferometry (VLBI) array that comprises millimeter- and submillimeter-wavelength telescopes separated by distances comparable to the diameter of the Earth. At a nominal operating wavelength of ∼1.3 mm, EHT angular resolution (λ/D) is ∼25 μas, which is sufficient to resolve nearby supermassive black hole candidates on spatial and temporal scales that correspond to their event horizons. With this capability, the EHT scientific goals are to probe general relativistic effects in the strong-field regime and to study accretion and relativistic jet formation near the black hole boundary. In this Letter we describe the system design of the EHT, detail the technology and instrumentation that enable observations, and provide measures of its performance. Meeting the EHT science objectives has required several key developments that have facilitated the robust extension of the VLBI technique to EHT observing wavelengths and the production of instrumentation that can be deployed on a heterogeneous array of existing telescopes and facilities. To meet sensitivity requirements, high-bandwidth digital systems were developed that process data at rates of 64 gigabit s -1 , exceeding those of currently operating cm-wavelength VLBI arrays by more than an order of magnitude. Associated improvements include the development of phasing systems at array facilities, new receiver installation at several sites, and the deployment of hydrogen maser frequency standards to ensure coherent data capture across the array. These efforts led to the coordination and execution of the first Global EHT observations in 2017 April, and to event-horizon-scale imaging of the supermassive black hole candidate in M87.

black hole physics

Galaxy: center

instrumentation: interferometers

gravitational lensing: strong

galaxies: individual (M87)

techniques: high angular resolution

Author

The Event Horizon Telescope Collaboration

Kazunori Akiyama

Harvard University

National Astronomical Observatory of Japan

National Radio Astronomy Observatory

Massachusetts Institute of Technology (MIT)

Antxon Alberdi

Institute of Astrophysics of Andalusia (IAA)

Walter Alef

Max Planck Society

K. Asada

National Taiwan University

R. Azulay

Universitat de Valencia

Max Planck Society

A. K. Baczko

Max Planck Society

David Ball

University of Arizona

Mislav Baloković

Harvard University

Harvard-Smithsonian Center for Astrophysics

John Barrett

Massachusetts Institute of Technology (MIT)

Dan Bintley

East Asian Observatory

Lindy Blackburn

Harvard University

Harvard-Smithsonian Center for Astrophysics

W. Boland

Nederlandse Onderzoekschool voor Astronomie (NOVA)

K. L. Bouman

Harvard University

Harvard-Smithsonian Center for Astrophysics

California Institute of Technology (Caltech)

G. C. Bower

Academia Sinica

M. Bremer

Institut de Radioastronomie Millimétrique (IRAM)

C. 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

D. Broguière

Institut de Radioastronomie Millimétrique (IRAM)

Thomas Bronzwaer

Radboud University

Do Young Byun

Korea Astronomy and Space Science Institute

University of Science and Technology (UST)

J. E. Carlstrom

University of Chicago

A. Chael

Harvard University

Harvard-Smithsonian Center for Astrophysics

Chi Kwan Chan

University of Arizona

S. Chatterjee

Cornell University

Koushik Chatterjee

University of Amsterdam

Ming Tang Chen

Academia Sinica

Yongjun Chen

Shanghai Astronomical Observatory

Chinese Academy of Sciences

I. Cho

University of Science and Technology (UST)

Korea Astronomy and Space Science Institute

Pierre Christian

Harvard-Smithsonian Center for Astrophysics

University of Arizona

John Conway

Chalmers, Space, Earth and Environment, Onsala Space Observatory

James M. Cordes

Cornell University

G. Crew

Massachusetts Institute of Technology (MIT)

Yuzhu Cui

The Graduate University for Advanced Studies (SOKENDAI)

National Astronomical Observatory of Japan

Jordy Davelaar

Radboud University

Mariafelicia De Laurentis

University of Naples Federico II

Goethe University Frankfurt

R. P. Deane

University of Pretoria

Rhodes University

Jessica Dempsey

East Asian Observatory

Gregory Desvignes

Max Planck Society

Jason Dexter

Max Planck Society

S. Doeleman

Harvard-Smithsonian Center for Astrophysics

Harvard University

Ralph P. Eatough

Max Planck Society

H.D. Falcke

Radboud University

V. Fish

Massachusetts Institute of Technology (MIT)

Ed Fomalont

National Radio Astronomy Observatory

R. Fraga-Encinas

Radboud University

P. Friberg

East Asian Observatory

Christian M. Fromm

Goethe University Frankfurt

J. L. Gomez

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 Waterloo

C. Goddi

Radboud University

Leiden University

R. Gold

Goethe University Frankfurt

Minfeng Gu

Shanghai Astronomical Observatory

Chinese Academy of Sciences

M. Gurwell

Harvard-Smithsonian Center for Astrophysics

K. Hada

National Astronomical Observatory of Japan

The Graduate University for Advanced Studies (SOKENDAI)

Michael H. Hecht

Massachusetts Institute of Technology (MIT)

R. Hesper

University of Groningen

Luis C. Ho

Beijing University of Technology

P. T. P. Ho

National Taiwan University

Mareki Honma

The Graduate University for Advanced Studies (SOKENDAI)

National Astronomical Observatory of Japan

Chih Wei L. Huang

National Taiwan University

Lei Huang

Shanghai Astronomical Observatory

Chinese Academy of Sciences

D. Hughes

National Institute of Astrophysics, Optics and Electronics

Shiro Ikeda

National Astronomical Observatory of Japan

The Institute of Statistical Mathematics

The Graduate University for Advanced Studies (SOKENDAI)

University of Tokyo

Makoto Inoue

National Taiwan University

S. Issaoun

Radboud University

David J. James

Harvard-Smithsonian Center for Astrophysics

Harvard University

Buell T. Jannuzi

University of Arizona

M. Janßen

Radboud University

Britton Jeter

University of Waterloo

Wu Jiang

Shanghai Astronomical Observatory

Michael D. Johnson

Harvard University

Harvard-Smithsonian Center for Astrophysics

S.G. Jorstad

Boston University

Saint Petersburg State University - Spsu

Taehyun Jung

University of Science and Technology (UST)

Korea Astronomy and Space Science Institute

Mansour Karami

Perimeter Institute for Theoretical Physics

University of Waterloo

R. Karuppusamy

Max Planck Society

Tomohisa Kawashima

National Astronomical Observatory of Japan

G. Keating

Harvard-Smithsonian Center for Astrophysics

M. M. Kettenis

Joint Institute for VLBI in Europe (JIVE)

Jae Young Kim

Max Planck Society

Junhan Kim

University of Arizona

Jongsoo Kim

Korea Astronomy and Space Science Institute

M. Kino

Kogakuin University of Technology and Engineering

National Astronomical Observatory of Japan

Jun Yi Koay

National Taiwan University

Patrick M. Koch

National Taiwan University

Shoko Koyama

National Taiwan University

M. Kramer

Max Planck Society

C. Kramer

Institut de Radioastronomie Millimétrique (IRAM)

T.P. Krichbaum

Max Planck Society

Cheng Yu Kuo

National Sun Yat-Sen University

Tod R. Lauer

National Optical Astronomy Observatory

Sang Sung Lee

Korea Astronomy and Space Science Institute

Yan Rong Li

Chinese Academy of Sciences

Zhiyuan Li

Nanjing University

Astrophysical Journal Letters

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

Vol. 875 1 L2

Subject Categories

Accelerator Physics and Instrumentation

Aerospace Engineering

Signal Processing

DOI

10.3847/2041-8213/ab0c96

More information

Latest update

4/1/2021 1