Weak Line Quasars at High Redshift: Extremely High Accretion Rates or Anemic Broad-line Regions?

  title={Weak Line Quasars at High Redshift: Extremely High Accretion Rates or Anemic Broad-line Regions?},
  author={Ohad Shemmer and Benny Trakhtenbrot and Scott F. Anderson and W. N. Brandt and Aleksandar M. Diamond-Stanic and Xiaohui Fan and P Lira and Hagai Netzer and Richard M. Plotkin and Gordon T. Richards and Donald P. Schneider and Michael A. Strauss U. North Texas and U. TelAviv and University of Washington and U. PennState and Penn State U. - Institute for Gravitation and The Cosmos and University of Arizona and Universidad Catolica de Chile and University of Amsterdam and U. Drexel and U. Princeton},
  journal={Journal of Leukocyte Biology},
We present Gemini-North K-band spectra of two representative members of the class of high-redshift quasars with exceptionally weak rest-frame ultraviolet emission lines (WLQs), SDSS J114153.34+021924.3 at z = 3.55 and SDSS J123743.08+630144.9 at z = 3.49. In both sources, we detect an unusually weak broad Hβ line and place tight upper limits on the strengths of their [O III] lines. Virial, Hβ-based black hole mass determinations indicate normalized accretion rates of L/L Edd=0.4 for these… Expand

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