The progenitors of planetary nebulae

Extract

Based on a new sample of (IRAS based) OH/IR stars (te Lintel Hekkert et al., 1991, A&AS, in press), and a catalogue of planetary nebulae compiled by Acker (1983, A&AS, 54, 315), we show the relation between these two groups of objects, in terms of the kinematics and the Galactic distribution. In contrast with earlier analyses of samples of OH/IR stars, we find a close correlation between the kinematics of the planetary nebulae and the IRAS based sample of OH/IR stars. In particular, we find that the distribution of the planetary nebulae (PN) shows a good correlation with the OH/IR stars which have a low outflow velocity (v_exp < 12.5 km s^–1). Whether the high outflow velocity OH/IR stars also have a counterpart among PN is not clear.