The formation of DA white dwarfs with thin hydrogen envelopes

L. G. ALTHAUS; M. M. MILLER BERTOLAMI; A. H. CÓRSICO; E. GARCÍA-BERRO; P. GIL-PONS

ASTRONOMY AND ASTROPHYSICS

EDP Sciences

Lugar: Les Ulis, France; Año: 2005 vol. 440 p. 1 - 4

0004-6361

We study  the  formation  and evolution of  DA white dwarfs, the progenitors  of which have  experienced a late thermal  pulse (LTP) shortly after  the departure from  the thermally pulsing AGB.  To this end,  we  compute the  complete  evolution  of  an initially  2.7 Mo  star all the  way from  the zero-age  main sequence  to the white dwarf stage.  We find that most of  the original H-rich material of the post-AGB  remnant is burnt during the  post-LTP evolution, with the  result that,  at  entering  its white  dwarf  cooling track,  the remaining H  envelope becomes 10E-6 Mo  in agreement with asteroseismological inferences for some ZZ Ceti stars.