While most of the scientific focus within the MWA consortium has been on frontier topics such as reionisation and transients, the project also marks a return to the early years of radio astronomy. In the 1940s and 1950s, astronomers in Australia built some of the first radio dishes and interferometers, which they used to map out the bright low-frequency radio emission from the diffuse Milky Way, and from individual discrete sources.
An inevitable by-product of any MWA observation will be new, high quality images of all these familiar classes of sources (in fact, the Milky Way and background galaxies will serve as the main foreground contaminant in the EoR experiment, and as a crucial set of background sources for studying the heliosphere and ionosphere). To take advantage of these rich data sets, a Galactic and Extragalactic (GEG) science team has now been assembled. The GEG team will carry out a diverse set of experiments aimed at obtaining a better understanding of supernova remnants (SNRs), HII regions, the diffuse interstellar medium, Galactic magnetic fields, and the energetics of external galaxies and clusters.
Most of these projects will capitalise on three main advantages of low-frequency astronomy: non-thermal sources will be very bright; Faraday rotation and depolarisation will be very strong; and along some sight lines free-free absorption will be significant. The combination of wide fields, good sensitivity and reasonable angular resolution will allow us to simultaneously study both small objects and large-scale structure.
Most GEG projects will rely on the multi-frequency all-sky survey maps that the team and the MWA project is proposing to provide. Some specific exceptions to this could be areas of deep polarisation mapping (for which the confusion limit will be ~20-30 times below that encountered in total intensity) and recombination line surveys (which require very high spectral resolution).
Chair: Dr Chenoa Tremblay (CSIRO)
|Science teams||Team leads||Contact|
|Prof. Melanie Johnston-Hollitt||Melanie.Johnston-Hollitt@curtin.edu.au|
|Galactic continuum||Dr Natasha Hurley-Walker|
|Magellanic clouds and nearby galaxies||Dr Ivy Wong|
|Polarimetry||Dr Xiang Zhang|
|Radio galaxies (AGN and star-forming galaxies)||Mr Ben Quici|
|Spectroscopy||Dr Chenoa Tremblay|
- Membership and GEG members
- Proposing a project and current project list
- GEG policy
- Published papers
- Talks and presentations
- Minutes of monthly GEG teleconferences