An Analysis of Ultraviolet Spectra of Extreme Helium Stars and New Clues to Their Origins

  title={An Analysis of Ultraviolet Spectra of Extreme Helium Stars and New Clues to Their Origins},
  author={Gajendra Pandey and David L. Lambert and C. Simon Jeffery and N. Kameswara Rao},
  journal={The Astrophysical Journal},
  pages={454 - 471}
Abundances of about 18 elements including the heavy elements Y and Zr are determined from Hubble Space Telescope Space Telescope Imaging Spectrograph ultraviolet spectra of seven extreme helium stars (EHes): LSE 78, BD +10 2179, V1920 Cyg, HD 124448, PV Tel, LS IV-1 2, and FQ Aqr. New optical spectra of BD +10 2179, V1920 Cyg, and HD 124448 were analyzed, and published line lists of LSE 78, HD 124448, and PV Tel were analyzed afresh. The abundance analyses are done using LTE line formation and… 

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