Low-Frequency Imaging of Fields at High Galactic Latitude with the Murchison Widefield Array 32 Element Prototype

Low-Frequency Imaging of Fields at High Galactic Latitude with the Murchison Widefield Array 32 Element Prototype

The Murchison Widefield Array (MWA) is a new low-frequency, wide-field-of-view radio interferometer under development at the Murchison Radio-astronomy Observatory in Western Australia. We have used a 32 element MWA prototype interferometer (MWA-32T) to observe two 50 degrees diameter fields in the s...

Full description

Bibliographic Details
Main Authors: Williams, C., Hewitt, J., Levine, A., de Oliveira-Costa, A., Bowman, Judd, Briggs, Frank, Gaensler, B., Hernquist, Lars, Mitchell, D., Morales, Miguel, Sethi, S., Subrahmanyan, R., Sadler, E., Arcus, Wayne, Barnes, David, Bernardi, G., Bunton, John, Cappallo, Roger, Crosse, B., Corey, Brian., Deshpande, Avinash, DeSouza, Ludi, Emrich, D., Goeke, Robert, Greenhill, L., Hazelton, Bryna, Herne, David, Kaplan, D., Kasper, Justin, Kincaid, Barton, Koenig, R., Kratzenberg, Eric, Lonsdale, Colin, Lynch, Mervyn, McWhirter, S., Morgan, Edward, Oberoi, Divya, Ord, Stephen, Pathikulangara, Joseph, Prabu, T., Remillard, Ron, Rogers, Alan, Roshi, Anish, Salah, J., Sault, R., Shankar, N Udaya, Srivani, K., Stevens, J., Tingay, Steven, Wayth, Randall, Waterson, Mark, Webster, Rachel, Whitney, Alan, Williams, A., Wyithe, J.
Format: Journal Article
Published: Institute of Physics Publishing, Inc. 2012
Subjects:
methods
data analysis
first stars
reionization
surveys
interferometers
instrumentation
dark ages
Online Access:http://hdl.handle.net/20.500.11937/30696
Description
Summary:The Murchison Widefield Array (MWA) is a new low-frequency, wide-field-of-view radio interferometer under development at the Murchison Radio-astronomy Observatory in Western Australia. We have used a 32 element MWA prototype interferometer (MWA-32T) to observe two 50 degrees diameter fields in the southern sky, covering a total of similar to 2700 deg(2), in order to evaluate the performance of the MWA-32T, to develop techniques for epoch of reionization experiments, and to make measurements of astronomical foregrounds. We developed a calibration and imaging pipeline for the MWA-32T, and used it to produce similar to 15' angular resolution maps of the two fields in the 110-200 MHz band. We perform a blind source extraction using these confusion-limited images, and detect 655 sources at high significance with an additional 871 lower significance source candidates. We compare these sources with existing low-frequency radio surveys in order to assess the MWA-32T system performance, wide-field analysis algorithms, and catalog quality. Our source catalog is found to agree well with existing low-frequency surveys in these regions of the sky and with statistical distributions of point sources derived from Northern Hemisphere surveys; it represents one of the deepest surveys to date of this sky field in the 110-200 MHz band.

Similar Items