Spotting high-z molecular absorbers using neutral carbon: Results from a complete spectroscopic survey with the VLT

  title={Spotting high-z molecular absorbers using neutral carbon: Results from a complete spectroscopic survey with the VLT},
  author={Pasquier Noterdaeme and C{\'e}dric Ledoux and Sheng Zou and Patrick Petitjean and Raghunathan Srianand and S. A. Balashev and Sebasti'an D. L'opez},
  journal={arXiv: Astrophysics of Galaxies},
While molecular quasar absorption systems provide unique probes of the physical and chemical properties of the gas as well as original constraints on fundamental physics and cosmology, their detection remains challenging. Here we present the results from a complete survey for molecular gas in thirty-nine absorption systems selected solely upon the detection of neutral carbon lines in SDSS spectra, without any prior knowledge of the atomic or molecular gas content. H2 is found in all twelve… 

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