Galaxies in the Local Volume conference poster
Centaurus A is by far the closest active supermassive black hole in the Universe, and has radio jet/lobe structures that span about 4 × 9 degrees on the sky. The greyscale image of NGC 5128 shown above, is the elliptical galaxy that hosts the radio source Centaurus A. The Very Large Array (VLA) radio continuum image of the inner jets of Centaurus A are also shown above, on the same scale as the optical image. These inner jets amount to less than 1% of the entire radio structure. The full radio morphology extends 4 x 9 degrees across the sky. So, why has Centaurus A never been fully imaged with an aperture synthesis telescope? Probably because the large angular size and the low surface brightness of the outer lobes make this project daunting, expensive in time and, up until recently, lacking in sophisticated software to deal with the high dynamic range and large field-of-view. The Compact Array really is the only array for the job, and finally it is being done!
Starting on 20 December 2006, we used the ATCA to mosaic - for the first time- the entire radio source at 20cm. We will mosaic the entire field in all four 750m configurations. To date we are half way through these observations (having observed with 750A and 750D).
Apart from producing the most detailed image ever of radio galaxy, our scientific aims are to:
(i) study the interaction of the radio source with the intergalactic medium,
(ii) Exploite Centuarus A as a background polarised screen to investigate the magnetic fields of foreground sources.
I will try to keep these pages updated with the current status of the project but if you would like further information, please send me an email.
1. The large-scale polarised structure of the outer lobes.
2. The influence of the radio lobes on the IGM.
3. A study of the interaction of the radio source with other dwarf galaxies in the Centaurus group.
4. A detailed study of the magnetic field properties of galaxies in the foreground of the radio lobes.
5. A detailed study of the magnetic field structure of the Milky Way using Centaurus A as a background polarising screen.
6. Dynamic range and new imaging techniques to produce the first high quality full size images of Centaurus A.
If you are interested in any of the above studies, or in joining the team and working on Centaurus A, then please contact one of the Team members below.
Ron Ekers (CSIRO ATNF)
Tim Cornwell (CSIRO ATNF)
Ray Norris (CSIRO ATNF)
Bryan Gaensler (USYD)
Juergen Ott (CSIRO ATNF)
Enno Middelberg (CSIRO ATNF)
Melanie Johnston-Hollitt (UTAS)
Joss Bland-Hawthorn (AAO)