• DOI:10.1086/340546
• Corpus ID: 15448823

Unusual Broad Absorption Line Quasars from the Sloan Digital Sky Survey

@article{Hall2002UnusualBA,
  title={Unusual Broad Absorption Line Quasars from the Sloan Digital Sky Survey},
  author={Patrick B. Hall and Scott F. Anderson and Michael A. Strauss and Donald G. York and Gordon T. Richards and Xiaohui Fan and Gillian R. Knapp and Donald P. Schneider and Daniel E. vanden Berk and Thomas R. Geballe and Amanda. E. Bauer and Robert H. Becker and Marc Davis and Hans–Walter Rix and Robert C. Nichol and Neta A. Bahcall and Jonathan Brinkmann and Robert J. Brunner and Andrew J. Connolly and Istv{\'a}n Csabai and Mamoru Doi and Masataka Fukugita and James E. Gunn and Zolt{\'a}n Haiman and Michael Harvanek and Timothy M. Heckman and Gregory S. Hennessy and Naohisa Inada and Željko Ivezi{\'c} and David E. Johnston and Scott J. Kleinman and Julian H. Krolik and Jurek Krzesinski and Peter Z. Kunszt and Donald Q. Lamb and Daniel C. Long and Robert H. Lupton and Gajus A. Miknaitis and Jeffrey A. Munn and Vijay K. Narayanan and Eric H. Neilsen and P. R. Newman and Atsuko Nitta and Sadanori Okamura and Laura Pentericci and Jeffrey R. Pier and David J. Schlegel and Stephanie A. Snedden and Alexander S. Szalay and Anirudda R. Thakar and Zlatan I. Tsvetanov and Richard L. White and Wei Zheng},
  journal={The Astrophysical Journal Supplement Series},
  year={2002},
  volume={141},
  pages={267 - 309}
}

• P. Hall, S. Anderson, +50 authors W. Zheng
• Published 15 March 2002
• Physics
• The Astrophysical Journal Supplement Series

The Sloan Digital Sky Survey has confirmed the existence of populations of broad absorption line (BAL) quasars with various unusual properties. We present and discuss 23 such objects and consider the implications of their wide range of properties for models of BAL outflows and quasars in general. We have discovered one BAL quasar with a record number of absorption lines. Two other similarly complex objects with many narrow troughs show broad Mg II absorption extending longward of their systemic host galaxy redshifts. This can be explained as absorption of an extended continuum source by the rotation-dominated base of a disk wind. Five other objects have absorption that removes an unprecedented ∼90% of all flux shortward of Mg II. The absorption in one of them has varied across the ultraviolet with an amplitude and rate of change as great as ever seen. This same object may also show broad Hβ absorption. Numerous reddened BAL quasars have been found, including at least one reddened mini-BAL quasar with very strong Fe II emission. The five reddest objects have continuum reddenings of E(B-V) ≃ 0.5, and in two of them we find strong evidence that the reddening curve is even steeper than that of the SMC. We have found at least one object with absorption from Fe III but not Fe II. This may be due to a high column density of moderately high ionization gas, but the Fe III level populations must also be affected by some sort of resonance. Finally, we have found two luminous, probably reddened high-redshift objects that may be BAL quasars whose troughs partially cover different regions of the continuum source as a function of velocity.