Prospects for Measuring Differential Rotation in White Dwarfs Through Asteroseismology

Details Prospects for Measuring Differential Rotation in White Dwarfs Through Asteroseismology Prospects for Measuring Differential Rotation in White Dwarfs Through Asteroseismology

1998-11-18

arxiv.org/abs/astro-ph/9811286v1

Astronomy and Astrophysics

Astrophysics

26 pages, 20 postscript figures. Accepted for publication in The Astrophysical Journal

Scientific paper

10.1086/307087

We examine the potential of asteroseismology for exploring the internal rotation of white dwarf stars. Data from global observing campaigns have revealed a wealth of frequencies, some of which show the signature of rotational splitting. Tools developed for helioseismology to use many solar p-mode frequencies for inversion of the rotation rate with depth are adapted to the case of more limited numbers of modes of low degree. We find that the small number of available modes in white dwarfs, coupled with the similarity between the rotational-splitting kernels of the modes, renders direct inversion unstable. Accordingly, we adopt what we consider to be plausible functional forms for the differential rotation profile; this is sufficiently restrictive to enable us to carry out a useful calibration. We show examples of this technique for PG 1159 stars and pulsating DB white dwarfs. Published frequency splittings for white dwarfs are currently not accurate enough for meaningful inversions; reanalysis of existing data can provide splittings of sufficient accuracy when the frequencies of individual peaks are extracted via least-squares fitting or multipeak decompositions. We find that when mode trapping is evident in the period spacing of g modes, the measured splittings can constrain dOmega/dr.

Affiliated with

Also associated with

No associations

Rating

Prospects for Measuring Differential Rotation in White Dwarfs Through Asteroseismology does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Prospects for Measuring Differential Rotation in White Dwarfs Through Asteroseismology, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Prospects for Measuring Differential Rotation in White Dwarfs Through Asteroseismology will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-515340