| Title | VLA Neutral Hydrogen Imaging of Compact Groups of Galaxies. II. HCG 31, 44, and 79 |
| Authors | Williams, B. A.; McMahon, P. M.; van Gorkom, J. H. |
| Bibcode | 1991AJ....101.1957W Search ADS ↗ |
| Abstract | We present images of the neutral hydrogen (H I) in the direction of the compact groups of galaxies, HCG 31, HCG 44, and HCG 79. In HCG 31 and HCG 79, emission is contained within clouds much larger than the galaxies as well as the entire group while the H I emission associated with HCG 44 is located within the individual galaxies. The H I morphology of these groups shows a clear physical association between the galaxies. A pattern may be emerging which describes their H I morphology. If compact groups are in the process of merging, we expect the smaller groups to be more evolved, i. e. nearer their coalescence. The least evolved group has H I gas that is still bound to the individual galaxies; although, clear signs of interaction are apparent in the gas. It is the more evolved groups that offer the surprising result. The individual "galaxies" which appear to be extremely small (dwarf) are embedded in a common envelope of gas. We observe the kinematics of the gas varying from ordered rotation in two groups to large systematic but apparently uncorrelated gradients in another. |
| Objects | 17 Objects Search NED ↙ |
