New cooling sequences for old hydrogen-rich white dwarfs

Abstract

We present fully evolutionary white dwarf cooling tracks for hydrogen‐rich DA white dwarfs. Our cooling sequences have been obtaind evolving white dwarf progenitors from the zero age main sequence, through the core hydrogen burning phase, the helium burning phase and the thermally pulsing asymptotic giant branch phase. Moreover, our evolutionary sequences are computed for a wide range of stellar masses and for two different metallicities: Z = 0.01 and Z = 0.001. The cooling sequences described here incorporate nuclear reactions during the early phases of white dwarf evolution, diffusion of the elements in the outer layers and, finally, all the relevant energy sources in the deep interior of the white dwarf, like the release of latent heat and the release of gravitational energy due to carbon‐oxygen phase separation upon crystallization. We also provide colors and magnitudes for these sequences, computed using non‐gray atmospheres, which include the Lyα quasi‐molecular opacity. The calculations are extended down to an effective temperature of 2,500 K.