The ALMA phasing system: A beamforming capability for ultra-high-resolution science at (sub)millimeter wavelengths
Journal article, 2018
The Atacama Millimeter/submillimeter Array (ALMA) Phasing Project (APP) has developed and deployed the hardware and software necessary to coherently sum the signals of individual ALMA antennas and record the aggregate sum in Very Long Baseline Interferometry (VLBI) Data Exchange Format. These beamforming capabilities allow the ALMA array to collectively function as the equivalent of a single large aperture and participate in global VLBI arrays. The inclusion of phased ALMA in current VLBI networks operating at (sub) millimeter wavelengths provides an order of magnitude improvement in sensitivity, as well as enhancements in u–v coverage and north–south angular resolution. The availability of a phased ALMA enables a wide range of new ultra-high angular resolution science applications, including the resolution of supermassive black holes on event horizon scales and studies of the launch and collimation of astrophysical jets. It also provides a high-sensitivity aperture that may be used for investigations such as pulsar searches at high frequencies. This paper provides an overview of the ALMA Phasing System design, implementation, and performance characteristics.
Methods: observational
Instrumentation: high angular resolution
Instrumentation: interferometers
Author
L. D. Matthews
Massachusetts Institute of Technology (MIT)
G. Crew
Massachusetts Institute of Technology (MIT)
S. Doeleman
Massachusetts Institute of Technology (MIT)
Harvard-Smithsonian Center for Astrophysics
R. Lacasse
National Radio Astronomy Observatory
A. F. Saez
Atacama Large Millimeter-submillimeter Array (ALMA)
W. Alef
Max Planck Society
K. Akiyama
National Astronomical Observatory of Japan
Massachusetts Institute of Technology (MIT)
R. Amestica
National Radio Astronomy Observatory
J. M. Anderson
Max Planck Society
German Research Centre for Geosciences (GFZ)
D. A. Barkats
Harvard-Smithsonian Center for Astrophysics
Atacama Large Millimeter-submillimeter Array (ALMA)
A. Baudry
University of Bordeaux
D. Broguière
Institut de Radioastronomie Millimétrique (IRAM)
R. Escoffier
National Radio Astronomy Observatory
V. Fish
Massachusetts Institute of Technology (MIT)
J. Greenberg
National Radio Astronomy Observatory
M. H. Hecht
Massachusetts Institute of Technology (MIT)
R. Hiriart
National Radio Astronomy Observatory Socorro
A. Hirota
Atacama Large Millimeter-submillimeter Array (ALMA)
M. Honma
The Graduate University for Advanced Studies (SOKENDAI)
National Astronomical Observatory of Japan
P. T.P. Ho
Academia Sinica
C. M. V. Impellizzeri
Atacama Large Millimeter-submillimeter Array (ALMA)
M. Inoue
Academia Sinica
Y. Kohno
National Astronomical Observatory of Japan
B. Lopez
Atacama Large Millimeter-submillimeter Array (ALMA)
Ivan Marti-Vidal
Chalmers, Space, Earth and Environment, Onsala Space Observatory
H. Messias
Atacama Large Millimeter-submillimeter Array (ALMA)
European Southern Observatory Santiago
Z. Meyer-Zhao
Academia Sinica
M. Mora-Klein
National Radio Astronomy Observatory
N. M. Nagar
University of Concepcion
H. Nishioka
Academia Sinica
T. Oyama
National Astronomical Observatory of Japan
V. Pankratius
Massachusetts Institute of Technology (MIT)
J. Perez
National Radio Astronomy Observatory
N. Phillips
Atacama Large Millimeter-submillimeter Array (ALMA)
N. Pradel
Academia Sinica
H. Rottmann
Max Planck Society
A. Roy
Max Planck Society
C. Ruszczyk
Massachusetts Institute of Technology (MIT)
B. Shillue
National Radio Astronomy Observatory
S. Suzuki
National Astronomical Observatory of Japan
R. Treacy
National Radio Astronomy Observatory
Publications of the Astronomical Society of the Pacific
0004-6280 (ISSN) 1538-3873 (eISSN)
Vol. 130 983 015002Subject Categories (SSIF 2011)
Other Computer and Information Science
Signal Processing
Other Electrical Engineering, Electronic Engineering, Information Engineering
DOI
10.1088/1538-3873/aa9c3d