Journal article
The 154 MHz radio sky observed by the Murchison Widefield Array: Noise, confusion, and first source count analyses
TMO Franzen, CA Jackson, AR Offringa, RD Ekers, RB Wayth, G Bernardi, JD Bowman, F Briggs, RJ Cappallo, AA Deshpande, BM Gaensler, LJ Greenhill, BJ Hazelton, M Johnston-Hollitt, DL Kaplan, CJ Lonsdale, SR McWhirter, DA Mitchell, MF Morales, E Morgan Show all
Monthly Notices of the Royal Astronomical Society | OXFORD UNIV PRESS | Published : 2016
DOI: 10.1093/mnras/stw823
Abstract
We analyse a 154 MHz image made from a 12 h observation with the Murchison Widefield Array (MWA) to determine the noise contribution and behaviour of the source counts down to 30 mJy. The MWA image has a bandwidth of 30.72 MHz, a field-of-view within the half-power contour of the primary beam of 570 deg2, a resolution of 2.3 arcmin and contains 13 458 sources above 5σ. The rms noise in the centre of the image is 4-5 mJy beam-1. The MWA counts are in excellent agreement with counts from other instruments and are the most precise ever derived in the flux density range 30-200 mJy due to the sky area covered. Using the deepest available source count data, we find that the MWA image is affected b..
View full abstractRelated Projects (2)
Grants
Awarded by National Science Foundation
Funding Acknowledgements
This work makes use of the Murchison Radioastronomy Observatory, operated by CSIRO. We acknowledge the Wajarri Yamatji people as the traditional owners of the Observatory site. We thank the anonymous referee for their suggestions, which have improved this paper. CAJ thanks the Department of Science, Office of Premier and Cabinet, WA for their support through the Western Australian Fellowship Programme. Support for the MWA comes from the US National Science Foundation (grants AST-0457585, PHY-0835713, CAREER-0847753, and AST-0908884), the Australian Research Council (LIEF grants LE0775621 and LE0882938), the US Air Force Office of Scientific Research (grant FA9550-0510247), and the Centre for All-sky Astrophysics (an Australian Research Council Centre of Excellence funded by grant CE110001020). Support is also provided by the Smithsonian Astrophysical Observatory, the MIT School of Science, the Raman Research Institute, the Australian National University, and the Victoria University of Wellington (via grant MED-E1799 from the New Zealand Ministry of Economic Development and an IBM Shared University Research Grant). The Australian Federal government provides additional support via the Commonwealth Scientific and Industrial Research Organization (CSIRO), National Collaborative Research Infrastructure Strategy, Education Investment Fund, and the Australia India Strategic Research Fund, and Astronomy Australia Limited, under contract to Curtin University. We acknowledge the iVEC Petabyte Data Store, the Initiative in Innovative Computing and the CUDA Center for Excellence sponsored by NVIDIA at Harvard University, and the International Centre for Radio Astronomy Research (ICRAR), a Joint Venture of Curtin University and The University of Western Australia, funded by the Western Australian State government.