Extreme abundance ratios in the polluted atmosphere of the cool white dwarf NLTT 19868

  title={Extreme abundance ratios in the polluted atmosphere of the cool white dwarf NLTT 19868},
  author={Adela Kawka and S. Vennes},
  journal={Monthly Notices of the Royal Astronomical Society},
  • A. Kawka, S. Vennes
  • Published 16 February 2016
  • Physics
  • Monthly Notices of the Royal Astronomical Society
We present an analysis of intermediate-dispersion spectra and photometric data of the newly identified cool, polluted white dwarf NLTT19868. The spectra obtained with X-shooter on the Very Large Telescope (VLT)-Melipal show strong lines of calcium, and several lines of magnesium, aluminium and iron. We use these spectra and the optical-to-near infrared spectral energy distribution to constrain the atmospheric parameters of NLTT19868. Our analysis shows that NLTT19868 is iron poor with respect… 

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