C, N, O abundances in the most metal-poor damped Lyman alpha systems★

  title={C, N, O abundances in the most metal-poor damped Lyman alpha systems★},
  author={Max Pettini and Berkeley J. Zych and Charles C. Steidel and Frederic H. Chaffee},
  journal={Monthly Notices of the Royal Astronomical Society},
This study focuses on some of the most metal-poor damped Lyα (DLA) absorbers known in the spectra of high-redshift QSOs, using new and archival observations obtained with ultraviolet-sensitive echelle spectrographs on the Keck and VLT telescopes. The weakness and simple velocity structure of the absorption lines in these systems allow us to measure the abundances of several elements, and in particular those of C, N and O, a group that is difficult to study in DLAs of more typical metallicities… Expand
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