One of the ATCA science drivers, identified
by the user community, is the study of "Galaxy Formation and Evolution" in
strong partnership with the Australian SKA Pathfinder (ASKAP). Three key areas
are:
- high-resolution mapping of the gas and dark matter in galaxies
- characterising black holes, quasars and radio galaxies
- low-surface brightness HI and CO mapping of nearby and distant galaxies, respectively.
The very short baselines between antennas, achieved by locating the 22-m dishes
of the Australia Telescope Compact Array (ATCA) very close to each other,
allow the mapping of very low-surface brightness atomic and molecular hydrogen
via the HI and CO spectral lines. Longer baselines filter out the diffuse
emission and often provide an incomplete picture. The HI 21-cm line is used to
map gas in relatively nearby galaxies while red-shifted CO lines can be used
to map the gas in much more distant galaxies. Four of the six ATCA dishes are
shown in the photo above. - For more information see the ATCA Future Science
Plan on the ATUC
pages.
The picture above is from Alex Cherney's (terrastro.com) ATCA video, available
on youtube.
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