Astronomy and Astrophysics – Astrophysics
Scientific paper
2007-06-20
Astronomy and Astrophysics
Astrophysics
Manuscript, 36 pages, 11 figures, accepted for publication in ApJ
Scientific paper
10.1086/520926
We present a comparative study of effective temperatures determined from the hydrogen Balmer lines and from the UV energy distribution for 140 DA white dwarfs drawn from the IUE archive. Our results indicate that the optical and UV temperatures of the majority of stars below T~40,000 K and within ~75 pc are in fairly good agreement given the uncertainties. At higher temperatures and/or larger distances, however, significant discrepancies are observed. Several mechanisms are investigated to account for these discrepancies including the effect of interstellar reddening, the presence of metals in the photosphere, and the existence of unresolved binary white dwarfs. The results of our analysis reveal that wavelength-dependent extinction is the most natural explanation for the observed temperature differences. We also attempt to predict the differences in optical and UV temperatures expected from unresolved degenerate binaries by performing an exhaustive simulation of composite model spectra. In light of these simulations, we then discuss some known double degenerates and identify new binary candidates by restricting our analysis to stars located within 75 pc where the effect of interstellar reddening is significantly reduced.
Bergeron Pierre
Lajoie Charles-Philippe
No associations
LandOfFree
A Comparative Study of Optical and Ultraviolet Effective Temperatures for DA White Dwarfs from the IUE Archive 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 A Comparative Study of Optical and Ultraviolet Effective Temperatures for DA White Dwarfs from the IUE Archive, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Comparative Study of Optical and Ultraviolet Effective Temperatures for DA White Dwarfs from the IUE Archive will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-34703