| 27th of July 2021 |
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| WALLABY observations of the Hydra Cluster |
| by Jing Wang |
|
Wang et al. have recently published a
study using ASKAP HI image data from the WALLABY pilot survey, covering
the Hydra cluster. They
identify that nearly two thirds of the galaxies may be in the
early stages of ram pressure stripping from their motions in the cluster.
A more detailed look at the subset of galaxies that are spatially
resolved in the WALLABY observations shows that, while it typically takes less than 200 Myr for ram
pressure stripping to remove the currently strippable portion of Hi, it may take more than 600 Myr to
significantly change the total Hi mass. The results provide new clues to understanding the different
rates of Hi depletion and star formation quenching in cluster galaxies.
The image above shows the WALLABY detected galaxies in the Hydra cluster. The Hi column density images are shown in different slices of velocity offset from the cluster center (∆vrad) around the X-ray halo of Hydra (grey scale). The column density images are enlarged by a factor of 5 for clarity. The paper has been published in The Astrophysical Journal. |