Galactic kinematics of planetary nebulae with [WC] central star

Abstract

High resolution spectra are used to analyze the galactic kinematics and distribution of a sample of planetary nebulae with [WR] and 'wel' central star ([WR]PN and WLPN). The circular and peculiar velocities (Vpec) of the objects were derived. The results are: a) [WR]PNe are distributed mainly in the galactic disk and they are more concentrated in a thinner disk than WLPNe and normal PNe, which corresponds to a younger population; b) the sample was separated in Peimbert's types, and it is found that Type I PNe have Vpec <50 km s-1, indicating young objects. Most of the [WR]PNe are of Type II showing Vpec <60 km s-1, although a small percentage is of Type III, with larger Vpec showing that the Wolf-Rayet phenomenon in central stars can occur at any stellar mass and in old objects. None of our WLPNe is Type I. Thus, [WR]PNe and WLPNe are unrelated objects.