HIGH-REDSHIFT SDSS QUASARS WITH WEAK EMISSION LINES

@article{DiamondStanic2009HIGHREDSHIFTSQ,
  title={HIGH-REDSHIFT SDSS QUASARS WITH WEAK EMISSION LINES},
  author={Aleksandar M. Diamond-Stanic and Xiaohui Fan and William Nielsen Brandt and Ohad Shemmer and Michael A. Strauss and Scott F. Anderson and Christopher L. Carilli and Robert R. Gibson and Linhua Jiang and J. Serena Kim and Gordon T. Richards and Gary D. Schmidt and Donald P. Schneider and Yue Shen and Paul S. Smith and Marianne Vestergaard and Jason E Young},
  journal={The Astrophysical Journal},
  year={2009},
  volume={699},
  pages={782 - 799}
}
We identify a sample of 74 high-redshift quasars (z > 3) with weak emission lines from the Fifth Data Release of the Sloan Digital Sky Survey and present infrared, optical, and radio observations of a subsample of four objects at z > 4. These weak emission-line quasars (WLQs) constitute a prominent tail of the Lyα + N v equivalent width distribution, and we compare them to quasars with more typical emission-line properties and to low-redshift active galactic nuclei with weak/absent emission… 

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