SDSS white dwarfs with spectra showing atomic oxygen and/or carbon lines

James Liebert, H. C. Harris, C. C. Dahn, Gary D. Schmidt, S. J. Kleinman, Atsuko Nitta, Jurek Krzesiński, Daniel Eisenstein, J. Allyn Smith, Paula Szkody, Suzanne Hawley, Scott F. Anderson, J. Brinkmann, Matthew J. Collinge, Xiaohui Fan, Patrick B. Hall, Gillian R. Knapp, Don Q. Lamb, B. Margon, Donald P. SchneiderNicole Silvestri

Research output: Contribution to journalArticle

34 Scopus citations

Abstract

We discuss 18 white dwarfs, one of which (G227-5) was previously known, whose SDSS spectra show lines of neutral and/or singly ionized carbon. At least two and perhaps four show lines of neutral or singly ionized oxygen. Apart from the extremely hot "PG 1159" stars, these are the first white dwarfs with photospheric oxygen detected in their optical spectra. The photometry strongly suggests that these stars lie in the 11,000-30,000 K temperature range of the helium-atmosphere DB white dwarfs, though only one of them shows weak neutral helium lines in the spectrum. Trigonometric parallaxes are known for G227-5 and another, previously known white dwarf (G35-26) showing atomic carbon lines, and they indicate that both are massive stars. Theoretical arguments suggest that all members of this class of rare white dwarfs are massive (∼1 M ), and this finding could explain the paucity of massive DB white dwarfs.

Original languageEnglish (US)
Pages (from-to)2521-2528
Number of pages8
JournalAstronomical Journal
Volume126
Issue number5 1775
DOIs
Publication statusPublished - Nov 2003

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Keywords

  • Stars: abundances
  • Stars: atmospheres
  • White dwarfs

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Liebert, J., Harris, H. C., Dahn, C. C., Schmidt, G. D., Kleinman, S. J., Nitta, A., ... Silvestri, N. (2003). SDSS white dwarfs with spectra showing atomic oxygen and/or carbon lines. Astronomical Journal, 126(5 1775), 2521-2528. https://doi.org/10.1086/378911