W. J. Maciel -
Abstract #70
THE G DWARF METALLICITY DISTRIBUTION AND THE PROBLEM OF STELLAR LIFETIMES LOWER THAN THE DISK AGE
H. J. Rocha-Pinto, W. J. Maciel
Astron. Astrophys. 325, 523-528 (1997) We examine the possibility of the inclusion of objects having lifetimes lower than the disk age in the database of recent determinations of the G dwarf metallicity distribution for the solar neighbourhood. As a preliminary step, stars with lifetimes potentially lower than the disk age are identified by means of a relation between (b-y), or mass, and [Fe/H], from evolutionary models of stars at the zero-age main sequence. We apply these results to the G dwarf samples of Rocha-Pinto and Maciel (1996) and Wyse and Gilmore (1995). We show that the majority of G dwarfs in these samples can be regarded as long-lived objects for chemical evolution purposes, provided the disk age is greater than 12 Gyr. We also find that the G dwarf problem is not an effect of the metallicity dependence of the stellar lifetimes.
