NLTE Spectral Analysis of GW Vir Pulsators
نویسنده
چکیده
GW Vir variables are the pulsating members in the spectroscopic class of the PG 1159 stars. In order to understand the characteristic differences between pulsating and non-pulsating PG1159 stars, we analyse FUSE spectra of eleven objects, of which six are pulsating, by means of state-of-the-art NLTE model atmospheres. The numerous metal lines in the FUV spectra of these stars allow a precise determination of the photospheric parameters. We present here preliminary results of our analysis.
منابع مشابه
High-resolution ultraviolet spectroscopy of PG 1159−035 with HST and FUSE
PG 1159−035 is the prototype of the PG1159 spectral class which consists of extremely hot hydrogen-deficient (pre) white dwarfs. It is also the prototype of the GW Vir variables, which are non-radial g-mode pulsators. The study of PG1159 stars reveals insight into stellar evolution and nucleosynthesis during AGB and post-AGB phases.
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