view Abstract Citations (25) References (35) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Extreme Ultraviolet Spectroscopy of G191-B2B: Direct Observation of Ionization Edges Wilkinson, Erik ; Green, James C. ; Cash, Webster Abstract We present the first spectrum of the hot, DA white dwarf G191-B2B (wd 0501 + 527) between 200 and 330 A. The spectrum, which has about 2 A resolution, was obtained with a sounding rocket-borne, grazing incidence spectrograph. The spectrum shows no evidence of He II, the expected primary opacity source in this wavelength region. Three ionization edges and one absorption feature were observed and are suggestive of O III existing in the photosphere of G191-B2B. Also noted is a broad spectral depression that may result from Fe VI in the photosphere. Publication: The Astrophysical Journal Pub Date: September 1992 DOI: 10.1086/186542 Bibcode: 1992ApJ...397L..51W Keywords: Stellar Spectra; Ultraviolet Spectroscopy; White Dwarf Stars; Absorption Spectra; Opacity; Photoionization; Photosphere; Stellar Atmospheres; Stellar Spectrophotometry; Astronomy; STARS: INDIVIDUAL ALPHANUMERIC: G191-B2B; ULTRAVIOLET: STARS; STARS: WHITE DWARFS full text sources ADS | data products SIMBAD (1)