Analysis of IUE spectra of helium-rich white dwarf stars

Autor(en): B G Castanheira, S O Kepler, Gerald Handler, D Koester
Abstrakt: We studied the class of DB white dwarf stars, using re-calibrated UV spectra for thirty four DBs obtained with the IUE satellite. By comparing the observed energy distributions with model atmospheres, we simultaneously determine spectroscopic distances (d), effective temperature (Teff), and surface gravities (log g). Using parallax measurements and previous determinations of Teff and log g from optical spectra, we can study whether the atmospheres of eleven DB stars are consistent with pure He or have a small amount of H contamination. We also report on our observations of seventeen stars with Teff close to the DB instability strip through time series photometry and found them to be non variable within our detection limits. Œ ESO 2006.
Organisation(en): Institut für Astrophysik
Externe Organisation(en): Universidade Federal do Rio Grande do Sul, Christian-Albrechts-Universität zu Kiel
Journal: Astronomy & Astrophysics
Band: 450
Seiten: 331-337
Anzahl der Seiten: 7
ISSN: 0004-6361
Publikationsdatum: 2006
Peer-reviewed: Ja
ÖFOS 2012: 103003 Astronomie
Link zum Portal: https://ucrisportal.univie.ac.at/de/publications/9482d332-e07f-4dfd-89b4-06553072e9da