2001/02/28 by V. Junkkarinen, G. A. Shields, E. A. Beaver +4 · 4 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Galaxies: Formation, Evolution, Phenomena #astro-ph
paper · pdf · doi:10.1086/319173
published as The Astrophysical Journal, 549:L155-L159, 2001 March 10 · 12 pages LATEX with 3 EPS figures; uses aaspp4.sty. Accepted for publication in The Astrophysical Journal Letters, volume 550 (2001 March 20)
arxiv created 2001/02/28 · openalex publication_date 2001/03/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
Imaging and spectroscopy with HST show that LBQS 0103-2753 (V = 17.8, z = 0.848) is a binary quasar with a separation of 0.3 arcsec or 2.3 kpc. This is by far the smallest separation binary quasar reported to date. The two components have very different spectra, including the presence of strong broad absorption lines (BALs) in component A only. The emission-line redshifts, based on the broad high ionization C IV lines, are zA = 0.834 and zB = 0.858; their difference is 3900 km/s in velocity units. The broad C IV lines, however, are probably not a good indicator of systemic redshift; and LBQS 0103-2753 A and B could have a much smaller systemic redshift difference, like the other known binary quasars. If the systemic redshift difference is small, then LBQS 0103-2753 would most likely be a galaxy merger that has led to a binary supermassive black hole. There is now one known 0.3 arcsec binary among roughly 500 QSOs that have been observed in a way that would reveal such a close binary. This suggests that QSO activity is substantially more likely for black hole binaries at spacings ~2 kpc than at ~15 to 60 kpc. Between 1987 and 1998, the observed Mg II BAL disappeared.