FUSE Spectroscopy of the DAO - type Central Star LS V + 4621 : Looking for the Photosphere in the Sea of Interstellar Absorption
نویسندگان
چکیده
The far-ultraviolet spectrum of the DAO White Dwarf LS V+4621, the exciting star of the possible planetary nebula Sh 2-216, is strongly contaminated by absorption features from the interstellar medium (ISM). For an ongoing spectral analysis, we aim to extract the pure photospheric spectrum in order to identify and model metal lines of species which are not detectable in the near-ultraviolet wavelength range. We have modeled the interstellar absorption precisely and considered it for the simulation of the FUSE (Far Ultraviolet Spectroscopic Explorer) observation. A state-of-the-art NLTE model-atmosphere spectrum which includes 16 elements is combined with the ISM absorption and then compared with the FUSE spectrum.
منابع مشابه
HST and FUSE Spectroscopy of the DAO - type Central Star LS V + 4621
The DAO-type white dwarf LS V+4621 is the hydrogen-rich central star of the possible planetary nebula Sh 2-216. We have taken high-resolution, high-S/N ultraviolet spectra with STIS aboard the HST and FUSE in order to constrain its photospheric parameters. A detailed spectral analysis by means of state-of-the-art NLTE model-atmosphere techniques is presented which includes the determination the...
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