W. J. Maciel -
Abstract #72
GRAVITY DISTANCES OF PLANETARY NEBULAE
W. J. Maciel, J. O. Cazetta
Astrophys. Space Sci. 249, 341-352 (1997) Recent work on the PN classification scheme initially proposed by Peimbert has shown that "type I" and "non-type I" objects have markedly different properties. Type I PN have He and N enrichments, lower heights relative to the galactic plane, and lower peculiar velocities, while non-type I nebulae have normal abundances and increasing heights and peculiar velocities. This implies some mass and age differences of the different types, which can be used in order to determine distances to disk PN. In this work, the behaviour of PN of different types on the log g x log Teff plane is explored, in view of the fact that central stars of different masses have different paths on this diagram. As a result, distances can be derived for some galactic PN, which can be compared with previous determinations. The possibility is discussed of establishing a statistical distance scale based on the population segregation of PN of different Peimbert types.
