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Abstract: We present full evolutionary calculations appropriate for the study ofhydrogen-rich DA white dwarfs. This is done by evolving white dwarf progenitorsfrom the zero age main sequence, through the core hydrogen burning phase, thehelium burning phase and the thermally pulsing asymptotic giant branch phase tothe white dwarf stage. Complete evolutionary sequences are computed for a widerange of stellar masses and for two different metallicities: Z=0.01, which isrepresentative of the solar neighborhood, and Z=0.001, which is appropriate forthe study of old stellar systems, like globular clusters. During the whitedwarf cooling stage we compute self-consistently the phase in which nuclearreactions are still important, the diffusive evolution of the elements in theouter layers and, finally, we also take into account all the relevant energysources in the deep interior of the white dwarf, like the release of latentheat and the release of gravitational energy due to carbon-oxygen phaseseparation upon crystallization. We also provide colors and magnitudes forthese sequences, based on a new set of improved non-gray white dwarf modelatmospheres, which include the most up-to-date physical inputs like the Lymanalpha quasi-molecular opacity. The calculations are extended down to aneffective temperature of 2,500 K. Our calculations provide a homogeneous set ofevolutionary cooling tracks appropriate for mass and age determinations of oldDA white dwarfs and for white dwarf cosmochronology of the different Galacticpopulations.



Autor: Isabel Renedo, Leandro G. Althaus, Marcelo M. Miller Bertolami, Alejandra D. Romero, Alejandro H. Corsico, Rene D. Rohrmann, Enri

Fuente: https://arxiv.org/



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