| Title | The H I content of galaxies in the Hercules supercluster: evidence for sweeping. |
| Authors | Giovanelli, R.; Chincarini, G. L.; Haynes, M. P. |
| Bibcode | 1981ApJ...247..383G Search ADS ↗ |
| Abstract | Arecibo observations of the neutral hydrogen content of 52 galaxies in the Hercules supercluster reveal signs of environmental dependence. Supercluster galaxies are compared with a sample of isolated galaxies with the same luminosity range, and galaxies found at large distances from the condensation appear to have normal M(H)/L ratios, while those near the cluster A2147 have marked deficiencies. The deficiencies contrast with the normal to mildly gas deficient A2151, which indicates that gas deficiency of spiral galaxies in Hercules is caused by removal due to ram pressure of the motion of galaxies through the intracluster medium. Calculations which take into account the intracluster medium density and velocity dispersion indicate the existence of a sweeping mechanism. Optical data also show that swept galaxies with more marked M(H)/L deficiencies tend to be redder than those with a normal ratio, especially in the case of Zw 108-072 in A2147. Results suggest that substantial galactic evolution may be catalyzed by opportune environmental conditions, and a large number of gas deficienct spiral galaxies undergo a gas-sweeping stage over a relatively short time scale. |
| Objects | 53 Objects Search NED ↙ |
