Asteroseismology of the Kepler V777 Her variable white dwarf with fully evolutionary models

Details Asteroseismology of the Kepler V777 Her variable white dwarf with fully evolutionary models Asteroseismology of the Kepler V777 Her variable white dwarf with fully evolutionary models

2011-12-26

arxiv.org/abs/1112.5882v3

Astronomy and Astrophysics

Astrophysics

Solar and Stellar Astrophysics

7 pages, 5 figures, 3 tables. To be published in Astronomy and Astrophysics

Scientific paper

DBV stars are pulsating white dwarfs with atmospheres rich in He. Asteroseismology of DBV stars can provide valuable clues about the origin, structure and evolution of hydrogen-deficient white dwarfs, and may allow to study neutrino and axion physics. Recently, a new DBV star, KIC 8626021, has been discovered in the field of the \emph{Kepler} spacecraft. It is expected that further monitoring of this star in the next years will enable astronomers to determine its detailed asteroseismic profile. We perform an asteroseismological analysis of KIC 8626021 on the basis of fully evolutionary DB white-dwarf models. We employ a complete set of evolutionary DB white-dwarf structures covering a wide range of effective temperatures and stellar masses. They have been obtained on the basis of a complete treatment of the evolutionary history of progenitors stars. We compute g-mode adiabatic pulsation periods for this set of models and compare them with the pulsation properties exhibited by KIC 8626021. On the basis of the mean period spacing of the star, we found that the stellar mass should be substantially larger than spectroscopy indicates. From period-to-period fits we found an asteroseismological model characterized by an effective temperature much higher than the spectroscopic estimate. In agreement with a recent asteroseismological analysis of this star by other authors, we conclude that KIC 8626021 is located near the blue edge of the DBV instability strip, contrarily to spectroscopic predictions. We also conclude that the mass of KIC 8626021 should be substantially larger than thought.

Affiliated with

Also associated with

No associations

Rating

Asteroseismology of the Kepler V777 Her variable white dwarf with fully evolutionary models 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 Asteroseismology of the Kepler V777 Her variable white dwarf with fully evolutionary models, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Asteroseismology of the Kepler V777 Her variable white dwarf with fully evolutionary models will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-253267