On the Purity of the ZZ Ceti Instability Strip: Discovery of More Pulsating DA White Dwarfs on the Basis of Optical Spectroscopy
نویسنده
چکیده
We report the discovery of two new ZZ Ceti pulsators, LP 133−144 and HE 1258+0123, selected on the basis of model atmosphere fits to optical spectroscopic data. The atmospheric parameters for LP 133−144, Teff = 11, 800 ± 200 K and log g = 7.87 ± 0.05, and for HE 1258+0123, Teff = 11, 410 ± 200 K and log g = 8.04 ± 0.05, place them within the empirical boundaries of the ZZ Ceti instability strip. This brings the number of known ZZ Ceti stars to a total of 36, a quarter of which have now been discovered using the spectroscopic approach for estimating their atmospheric parameters. This method has had a 100% success
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