| Title | Neutral hydrogen in groups of galaxies. I. The inner M 101 group. |
| Authors | Davies, R. D.; Davidson, G. P.; Johnson, S. C. |
| Bibcode | 1980MNRAS.191..253D Search ADS ↗ |
| Abstract | Neutral hydrogen observations have been made with a 12 x 12 arcmin angular resolution of the galaxies in the immediate neighbourhood of M101, namely NGC5474, NGC5477 and HolmbergIV. A detailed survey of 0°.6 × 0°.7 field around NGC 5474 confirmed the presence of distributed intra-cluster neutral hydrogen detected by Huchtmeier & Witzel (1979) and revealed several new features. It is estimated that about 10 per cent of the hydrogen in this group of galaxies lies outside their optical confines; it probably originates in the tidal stripping of the galaxies. The neutral hydrogen velocity and position data are used to derive the total mass of individual galaxies. A comparison of these masses with the mass of the group of galaxies derived from the virial theorem indicates that no appreciable hidden mass is required to bind the group. The virial mass-to-luminosity ratio is 14Msun/Lsun, a value comparable to the M/L ratio for the individual galaxies. |
| Objects | 4 Objects Search NED ↙ |
