Formacion de Enanas Blancas DA con envolturas delgadas de hidrogeno.

M. M. MILLER BERTOLAMI, L. G. ALTHAUS Y A. H. CORSICO.

La Plata

Congreso; 48ava Reunion Anual de la Asociacion Argentina de Astronomia; 2005

Facultad de Ciencias Astronomicas y Geofisicas - IAR

We study the formation and evolution of DA white dwarfs, whose progenitor have experienced a Late Thermal Pulse (LTP) after the departure from the thermally pulsing Asymptotic Giant Branch. To this end, we compute the complete evolution of an initially 2.7 M star from the Zero Age Main Sequence through the thermally pulsing AGB and up to the ZZ Ceti domain in the white dwarf cooling track. We nd that most of the H-rich material of the post-AGB remnant star is burnt during the post-LTP evolution, with the result that, at entering the ZZ-ceti domain the remaining H envelope becomes 4 10��710��7 M . In addition we studied the eect of possible mass loss rates during the PG1159 stage on the nal H-mass of the star. We also add an appendix regarding an observation from the audience. . In addition we studied the eect of possible mass loss rates during the PG1159 stage on the nal H-mass of the star. We also add an appendix regarding an observation from the audience.