Serendipitous discovery of a projected pair of QSOs separated by 4.5 arcsec on the sky

Abstract

We present the serendipitous discovery of a projected pair of quasi-stellar objects (QSOs) with an angular separation of $\Delta \theta =4.50$ arcsec. The redshifts of the two QSOs are widely different: one, our programme target, is a QSO with a spectrum consistent with being a narrow line Seyfert 1 AGN at $z=2.05$. For this target we detect Lyman-$\alpha$, \ion{C}{4}, and \ion{C}{3]}. The other QSO, which by chance was included on the spectroscopic slit, is a Type 1 QSO at a redshift of $z=1.68$, for which we detect \ion{C}{4}, \ion{C}{3]} and \ion{Mg}{2}. We compare this system to previously detected projected QSO pairs and find that only about a dozen previously known pairs have smaller angular separation.

arXiv comment4 pages, 3 figures. Accepted for publication in AJ

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Cited by in corpus (2)

• The extended High A(V) Quasar Survey: Searching for dusty absorbers toward mid-infrared selected quasars
• Serendipitous discovery of a physical binary quasar at z=1.76