An FeLoBAL binary quasar

Michael D. Gregg, Robert H. Becker, Richard L. White, Gordon T. Richards, Fred H. Chaffee, Xiaohui Fan

Research output: Contribution to journalArticlepeer-review

25 Scopus citations


In an ongoing infrared imaging survey of quasars at the Keck Observatory, we have discovered that the z = 1.285 quasar SDSS J233646.2-010732.6 comprises two point sources with a separation of 1″.67. Resolved spectra show that one component is a standard quasar with a blue continuum and broad emission lines; the other is a broad absorption line (BAL) quasar, specifically, a BAL QSO with prominent absorption from Mg II and metastable Fe II, making it a member of the "FeLoBAL" class. The number of known FeLoBALs has recently grown dramatically from a single example to more than a dozen, including a gravitationally lensed example and the binary member presented here, suggesting that this formerly rare object may be fairly common. Additionally, the presence of this BAL quasar in a relatively small separation binary adds to the growing evidence that the BAL phenomenon is not due to viewing a normal quasar at a specific orientation but rather that it is an evolutionary phase in the life of many, if not all, quasars and is particularly associated with conditions found in interacting systems.

Original languageEnglish (US)
Pages (from-to)L85-L89
JournalAstrophysical Journal
Issue number2 II
StatePublished - Jul 10 2002


  • Galaxies: interactions
  • Quasars: absorption lines
  • Quasars: general

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


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