GMIMS-DRAGONS: A Faraday Depth Survey of the Northern Sky Covering 350-1030 MHz
Artikel i vetenskaplig tidskrift, 2026
Polarized synchrotron emission at meter to centimeter wavelengths provides an effective tracer of the Galactic magnetic field. Calculating Faraday depth, the most useful parameter for mapping the line-of-sight magnetic field, requires observations covering wide frequency bands with many channels. As part of the Global Magneto-Ionic Medium Survey (GMIMS), we have observed polarized emission spanning 350-1030 MHz over the northern sky, in the declination range -20 degrees <= delta <= 90 degrees. We used the 15 m telescope at the Dominion Radio Astrophysical Observatory (DRAO), equipped to receive orthogonal circular polarizations, with the Onsala Space Observatory band 1 feed developed for the SKA Project. Angular resolution varies across the band from 1 .degrees 3 to 3 .degrees 6. A digital spectrometer provided 42 kHz frequency resolution. Data were taken with the telescope moving rapidly in azimuth and are absolutely calibrated in intensity. Approximately 25% of the data were lost due to radio-frequency interference. The resolution in Faraday depth is similar to 6 rad m-2, and features as wide as similar to 38 rad m-2 are represented. The median sensitivity of the Faraday depth cube is 11 mK. Approximately 55% of sight lines in this survey show Faraday complexity. This dataset, called "DRAO GMIMS of the Northern Sky," is the first to probe Faraday depth of the northern sky in its frequency range and will support many scientific investigations. The data will be used to calibrate surveys with higher angular resolution, particularly Galactic foreground maps from the Canadian Hydrogen Intensity Mapping Experiment, and to provide information on large structures for aperture-synthesis telescopes, particularly the DRAO Synthesis Telescope. The data are available through the Canadian Astronomy Data Centre.
Författare
Anna Ordog
National Research Council Canada
University of British Columbia (UBC)
Western University
Rebecca A. Booth
University of Calgary
T. L. Landecker
National Research Council Canada
Ettore Carretti
Istituto nazionale di astrofisica (INAF)
Alex S. Hill
National Research Council Canada
University of British Columbia (UBC)
Jo-Anne C. Brown
University of Calgary
Artem Davydov
University of Calgary
Leonardo Moutinho Caffarello
University of British Columbia (UBC)
Luca B. Galler
University of Waterloo
University of Calgary
Jonas Flygare
Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium
Jennifer L. West
National Research Council Canada
A. G. Willis
National Research Council Canada
Mehrnoosh Tahani
University of South Carolina
Gary Hovey
Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium
Dustin Lagoy
National Research Council Canada
Stephen Harrison
National Research Council Canada
Michael A. Smith
National Research Council Canada
Charl Baard
National Research Council Canada
Rob H. Messing
National Research Council Canada
D. A. Del Rizzo
National Research Council Canada
Benoit Robert
National Research Council Canada
Timothy Robishaw
National Research Council Canada
John M. Dickey
University of Tasmania
George Morgan
University of British Columbia (UBC)
Ian R. Kennedy
University of British Columbia (UBC)
Marijke Haverkorn
Radboud Universiteit
Andrea Bracco
Université Paris Descartes
Istituto nazionale di astrofisica (INAF)
John Conway
Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium
Astrophysical Journal, Supplement Series
0067-0049 (ISSN) 1538-4365 (eISSN)
Vol. 282 2 53Ämneskategorier (SSIF 2025)
Astronomi, astrofysik och kosmologi
DOI
10.3847/1538-4365/ae2471
Relaterade dataset
GMIMS-DRAGONS: A Faraday Depth Survey of the Northern Sky Covering 350 to 1030 MHz [dataset]
DOI: 10.11570/25.0104