Observations of H I absorbing gas in compact radio sources at cosmological redshifts

@article{Vermeulen2003ObservationsOH,
  title={Observations of H I absorbing gas in compact radio sources at cosmological redshifts},
  author={Ren{\'e} C. Vermeulen and Y. M. Pihlstroem and Wolfgang Tschager and Willem Hendrik de Vries and J. Conway and Peter Barthel and S. A. Baum and Robert Joseph Braun and Malcolm N. Bremer and George K. Miley and Christopher P. O’Dea and Huub J. A. Roettgering and Richard T. Schilizzi and I. A. G. Snellen and Gregory B. Taylor},
  journal={Astronomy and Astrophysics},
  year={2003},
  volume={404},
  pages={861-870}
}
We present an overview of the occurrence and properties of atomic gas associated with compact radio sources at redshifts up to z = 0.85. Searches for H i 21cm absorption were made with the Westerbork Synthesis Radio Telescope at UHF-high frequencies (725-1200 MHz). Detections were obtained for 19 of the 57 sources with usable spectra (33%). We have found a large range in line depths, from � = 0.16 to � � 0.001. There is a substantial variety of line profiles, including Gaussians of less than… 

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