Title | The spindle-like galaxies UGC 7576 and II ZW 73. |
Authors | Schechter, P. L.; Sancisi, R.; van Woerden, H.; Lynds, C. R. |
Bibcode | 1984MNRAS.208..111S Search ADS ↗ |
Abstract | The spindle-like galaxies UGC 7576 and II Zw 73 in the 21-cm line of neutral hydrogen have been mapped. In both systems the projected H I distribution coincides almost perfectly with the projected light distribution of the outer optical component. The velocity fields in both objects support the identification of the outer components as differentially rotating annuli seen edge-on. The hydrogen mass-optical luminosity ratios in these components are exceptionally large. The annuli exhibit little or no evidence of differential precession, yet the time-scales for this process (granting reasonable assumptions about the shapes of the gravitational potentials) are relatively short. The annuli therefore appear to have formed in the relatively recent past. |
Objects | 5 Objects Search NED ↙ |