First 230? GHz VLBI fringes on 3C 279 using the APEX Telescope (Research Note)
Journal article, 2015

Aims. We report about a 230? GHz very long baseline interferometry (VLBI) fringe finder observation of blazar 3C 279 with the APEX telescope in Chile, the phased submillimeter array (SMA), and the SMT of the Arizona Radio Observatory (ARO). Methods. We installed VLBI equipment and measured the APEX station position to 1? cm accuracy (1σ). We then observed 3C 279 on 2012 May 7 in a 5? h 230? GHz VLBI track with baseline lengths of 2800? Mλ to 7200? Mλ and a finest fringe spacing of 28.6? μas. Results. Fringes were detected on all baselines with signal-to-noise ratios of 12 to 55 in 420? s. The correlated flux density on the longest baseline was ∼0.3? Jy beam-1, out of a total flux density of 19.8? Jy. Visibility data suggest an emission region ≤ 38? μas in size, and at least two components, possibly polarized. We find a lower limit of the brightness temperature of the inner jet region of about 1010? K. Lastly, we find an upper limit of 20% on the linear polarization fraction at a fringe spacing of ∼ 38? μas. Conclusions. With APEX the angular resolution of 230? GHz VLBI improves to 28.6? μas. This allows one to resolve the last-photon ring around the Galactic Center black hole event horizon, expected to be 40? μas in diameter, and probe radio jet launching at unprecedented resolution, down to a few gravitational radii in galaxies like M 87. To probe the structure in the inner parsecs of 3C 279 in detail, follow-up observations with APEX and five other mm-VLBI stations have been conducted (March 2013) and are being analyzed.

Telescopes

Galaxies: individual: 3C 279

Instrumentation: high angular resolution

Galaxies: jets

Author

Jan Wagner

Max Planck Institute

Korea Astronomy and Space Science Institute

A. Roy

Max Planck Institute

T.P. Krichbaum

Max Planck Institute

W. Alef

Max Planck Institute

A. Bansod

Max Planck Institute

A. Bertarini

Max Planck Institute

University of Bonn

R. Güsten

Max Planck Institute

D. Graham

Max Planck Institute

J. Hodgson

Max Planck Institute

R. Märtens

Max Planck Institute

K. Menten

Max Planck Institute

D. Muders

Max Planck Institute

H. Rottmann

Max Planck Institute

G. Tuccari

Istituto nazionale di astrofisica (INAF)

Max Planck Institute

A. Weiss

Max Planck Institute

G. Wieching

Max Planck Institute

M. Wunderlich

Max Planck Institute

A.J. Zensus

Max Planck Institute

J.P. Araneda

European Southern Observatory Santiago

O. Arriagada

European Southern Observatory Santiago

M. Cantzler

European Southern Observatory Santiago

C. Duran

European Southern Observatory Santiago

F.M. Montenegro-Montes

European Southern Observatory Santiago

R. Olivares

European Southern Observatory Santiago

P. Caro

Per Bergman

Chalmers, Earth and Space Sciences, Onsala Space Observatory

John Conway

Chalmers, Earth and Space Sciences, Onsala Space Observatory

Rüdiger Haas

Chalmers, Earth and Space Sciences, Onsala Space Observatory

Jan Johansson

Chalmers, Earth and Space Sciences, Space Geodesy and Geodynamics

Michael Lindqvist

Chalmers, Earth and Space Sciences, Onsala Space Observatory

Hans Olofsson

Chalmers, Earth and Space Sciences, Onsala Space Observatory

Miroslav Pantaleev

Chalmers, Earth and Space Sciences, Onsala Space Observatory

S. Buttaccio

Istituto nazionale di astrofisica (INAF)

R. Cappallo

Massachusetts Institute of Technology (MIT)

G. Crew

Massachusetts Institute of Technology (MIT)

S. Doeleman

Massachusetts Institute of Technology (MIT)

V. Fish

Massachusetts Institute of Technology (MIT)

R.S. Lu

Massachusetts Institute of Technology (MIT)

C. Ruszczyk

Massachusetts Institute of Technology (MIT)

J. SooHoo

Massachusetts Institute of Technology (MIT)

M. Titus

Massachusetts Institute of Technology (MIT)

R. Freund

University of Arizona

D. P. Marrone

University of Arizona

P. Strittmatter

University of Arizona

L. Ziurys

University of Arizona

R. Blundell

Harvard-Smithsonian Center for Astrophysics

R. Primiani

Harvard-Smithsonian Center for Astrophysics

J. Weintroub

Harvard-Smithsonian Center for Astrophysics

K. Young

Harvard-Smithsonian Center for Astrophysics

M. Bremer

Institut de RadioAstronomie Millimetrique (IRAM)

S. Sánchez

Instituto de Radioastronomía Milimétrica

A.P. Marscher

Boston University

R. Chilson

Academia Sinica

K. Asada

Academia Sinica

M. Inoue

Academia Sinica

Astronomy and Astrophysics

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

Vol. 581 A32

Subject Categories

Fusion, Plasma and Space Physics

DOI

10.1051/0004-6361/201423613

More information

Latest update

4/4/2019 1