Previous abstract Next abstract

Session 18 - White Dwarfs.
Display session, Monday, January 15
North Banquet Hall, Convention Center

[18.03] Asteroseismology of Individual Cool DAVs.

S. J. Kleinman (Univ. Texas Austin)

The white dwarfs are promising laboratories for the study of cosmochronology and stellar evolution. Through observations of the pulsating white dwarfs, we can actually measure the white dwarf cooling rates, directly calibrating their ages. The most important set of white dwarf variables to measure are the coolest of the pulsators, the cool DAVs, which have not previously been explored through asteroseismology due to their complexity and instability. Through a time-series photometry data set that spans nine years, I explore the pulsation spectrum of the cool DAV, G29--38 and find an underlying structure of normal-mode, \ell=1 pulsations amidst an abundance of time variability and linear combination modes. Similar, although less complete results were obtained for other cool DAVs, such as G191--16 and HL Tau 76. The H-layer masses of these stars is likely near 10^-4 M\lower.5ex\hbox\star. We now know the structure of the cool DAVs and can use these in our cooling and stellar evolution models.

Program listing for Monday