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arXiv · 1410.0790

The Murchison Widefield Array Commissioning Survey: A Low-Frequency Catalogue of 14,110 Compact Radio Sources over 6,100 Square Degrees

Natasha Hurley-Walker·John Morgan·Randall B. Wayth·Paul J. Hancock·Martin E. Bell·Gianni Bernardi·Ramesh Bhat·Frank Briggs·Avinash A. Deshpande·Aaron Ewall-Wice·Lu Feng·Bryna J. Hazelton·Luke Hindson·Daniel C. Jacobs·David L. Kaplan Nadia Kudryavtseva·Emil Lenc·Benjamin McKinley·Daniel Mitchell·Bart Pindor·Pietro Procopio·Divya Oberoi·André Offringa·Stephen Ord·Jennifer Riding·Judd D. Bowman·Roger Cappallo·Brian Corey·David Emrich·B. M. Gaensler·Robert Goeke·Lincoln Greenhill·Jacqueline Hewitt·Melanie Johnston-Hollitt·Justin Kasper·Eric Kratzenberg·Colin Lonsdale·Mervyn Lynch·Russell McWhirter·Miguel F. Morales·Edward Morgan·Thiagaraj Prabu·Alan Rogers·Anish Roshi·Udaya Shankar·K. Srivani·Ravi Subrahmanyan·Steven Tingay·Mark Waterson·Rachel Webster·Alan Whitney·Andrew Williams·Chris Williams
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Abstract

We present the results of an approximately 6,100 square degree 104--196MHz radio sky survey performed with the Murchison Widefield Array during instrument commissioning between 2012 September and 2012 December: the Murchison Widefield Array Commissioning Survey (MWACS). The data were taken as meridian drift scans with two different 32-antenna sub-arrays that were available during the commissioning period. The survey covers approximately 20.5 h < Right Ascension (RA) < 8.5 h, -58 deg < Declination (Dec) < -14 deg over three frequency bands centred on 119, 150 and 180 MHz, with image resolutions of 6--3 arcmin. The catalogue has 3-arcmin angular resolution and a typical noise level of 40 mJy/beam, with reduced sensitivity near the field boundaries and bright sources. We describe the data reduction strategy, based upon mosaiced snapshots, flux density calibration and source-finding method. We present a catalogue of flux density and spectral index measurements for 14,110 sources, extracted from the mosaic, 1,247 of which are sub-components of complexes of sources.

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Natasha Hurley-Walker, John Morgan, Randall B. Wayth, Paul J. Hancock, Martin E. Bell, Gianni Bernardi, Ramesh Bhat, Frank Briggs, Avinash A. Deshpande, Aaron Ewall-Wice, Lu Feng, Bryna J. Hazelton, Luke Hindson, Daniel C. Jacobs, David L. Kaplan Nadia Kudryavtseva, Emil Lenc, Benjamin McKinley, Daniel Mitchell, Bart Pindor, Pietro Procopio, Divya Oberoi, André Offringa, Stephen Ord, Jennifer Riding, Judd D. Bowman, Roger Cappallo, Brian Corey, David Emrich, B. M. Gaensler, Robert Goeke, Lincoln Greenhill, Jacqueline Hewitt, Melanie Johnston-Hollitt, Justin Kasper, Eric Kratzenberg, Colin Lonsdale, Mervyn Lynch, Russell McWhirter, Miguel F. Morales, Edward Morgan, Thiagaraj Prabu, Alan Rogers, Anish Roshi, Udaya Shankar, K. Srivani, Ravi Subrahmanyan, Steven Tingay, Mark Waterson, Rachel Webster, Alan Whitney, Andrew Williams, Chris Williams. 2014-10-03. The Murchison Widefield Array Commissioning Survey: A Low-Frequency Catalogue of 14,110 Compact Radio Sources over 6,100 Square Degrees. https://doi.org/10.1017/pasa.2014.40

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