25th of January 2021 |
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ATCA imaging of Choir groups |
by Dzudzar et al. |
SINGG -- the Survey of Ionization in Neutral Gas Galaxies --
entailed optical imaging of 468 HIPASS detections.
Inspection of the SINGG images revealed 15
fields that had four or more emission line galaxies within the 15 arcminute
HIPASS beam, and these SINGG groups were naturally named "Choirs"!
Dzudzar et al. have used the ATCA to study the HI content of
Choir groups.
The image above shows the HI emission in the HIPASS J0205-55 Choir group.
The HI emission is shown by the contours overlaid on the DSS2Red optical
image. The lowest shown HI column density is a 3σ detection over a velocity width of 15 km/s
and corresponds to 1.5×10^19 cm^−2. The
other HI column density contours are: 7, 14, 21, 28 and 35×10^19 cm−2.
The synthesized
beam is shown in the bottom left corner, and the scale bar in the bottom right corner shows 50 kpc at the group distance.
More details are give in
the paper by Dzudzar et al.,
published in Monthly Notices of the Royal Astronomical Society.
As tomorrow is the Australia Day public holiday, the next ADAP will appear on January 27th. |