Serendipitous Discovery of a Projected Pair of QSOs Separated by 4.5 arcsec on the Sky

Heintz, K. E.; Fynbo, J. P. U.; Krogager, J.-K.; Vestergaard, M.; Møller, P.; Arabsalmani, M.; Geier, S.; Noterdaeme, P.; Ledoux, C.; Saturni, F. G.; Venemans, B.
Referencia bibliográfica

The Astronomical Journal, Volume 152, Issue 1, article id. 13, pp. (2016).

Fecha de publicación:
7
2016
Número de autores
11
Número de autores del IAC
1
Número de citas
2
Número de citas referidas
2
Descripción
We present the serendipitous discovery of a projected pair of quasi-stellar objects (QSOs) with an angular separation of Δθ = 4.50 arcsec. The redshifts of the two QSOs are widely different: one, our program target, is a QSO with a spectrum consistent with being a narrow line Seyfert 1 active galactic nucleus at z = 2.05. For this target we detect Lyα, C iv, and C iii]. 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 C iv, C iii], and Mg ii. We compare this system to previously detected projected QSO pairs and find that only about a dozen previously known pairs have smaller angular separation. Based on observations made with the Nordic Optical Telescope, on the island of La Palma jointly operated by Denmark, Finland, Iceland, Norway, and Sweden, in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias.