We present detailed evolutionary calculations for CO- and helium- core white dwarf (WD) models with masses ranging from M= 0.1 to M= 1.2 and for metallicities Z= 0.001 and Z= 0. The sequences cover a wide range of hydrogen envelopes as well. We employed a detailed WD evolutionary code. In particular, the energy transport by convection is treated within the formalism of the full spectrum turbulence theory. Convective mixing, crystallization, hydrogen burning and neutrino energy losses are considered. The set of models presented here is very detailed and should be valuable for the interpretation of the observational data about low mass WDs recently discovered in numerous binary configurations and also for the general problem of determining the theoretical luminosity function for WDs. In this context, we compare our cooling sequences to the observed WD luminosity function recently improved by Leggett, Ruiz and Bergeron (1998) and we obtain an age for the Galactic disk of approximately 8 Gyr. Finally, we applied our models to derive stellar masses of a sample of low mass WDs.
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