16th of March 2015 |
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The "tail" of ESO 324-G024 |
by Megan Johnson (CASS) |
ESO 324-G024 is a dwarf irregular galaxy in
the Centaurus A galaxy group and lies only ~104 kpc from the center of
NGC 5128, which is the giant elliptical galaxy and host to the radio source
known as Centaurus A. We find that ESO 324-G024 has a peculiar
neutral hydrogen morphology with a long tail-like structure that extends
2.5 kpc beyond its disk. We find evidence that ESO 324-G024 likely passed
through the northern radio lobe of Cen A and has experienced ram pressure
forces, which are likely the dominant mechanism for creating its tail. In
this figure, we see ESO 324-G024 (white contour) superimposed on Cen A's
giant radio lobe (A) together with a zoom-in of the velocity field of
ESO 324-G024 (B) and its optical stellar component (C). The contours in
panels B and C are of the neutral hydrogen intensity. ESO324-G024 is one of around 80 southern galaxies studied with the Australia Telescope Compact Array (ATCA) as part of the Local Volume HI Survey (LVHIS). Megan Johnson will be present this work today at the 8th PHISCC Workshop. |