English

The First Observations of the Second Brightest Quasar

Astrophysics 2009-11-06 v1

Abstract

We report the discovery of a new bright quasar PHL 1811 as part of a followup program to identify bright quasars in the FIRST radio survey. With B=13.9, R=13.9, and z=0.192, this quasar is now the second brightest quasar (in apparent magnitude) known beyond z=0.1. Optically classified as a Narrow-line Seyfert 1 galaxy (NLS1), PHL 1811 is unusual for an object in this class in that it was not detected in X-rays in the ROSAT All Sky survey or in any previous X-ray survey. A follow-up BeppoSAX observation confirms that it is deficient in X-rays compared with other quasars, but poor signal to noise prevents a definitive characterization of the X-ray spectrum. We consider three alternative hypotheses to explain why PHL 1811 is a weak X-ray source: 1.) it is a BALQSO and suffers X-ray absorption; 2.) like several other luminous NLS1s, it exhibits high amplitude X-ray variability, and has been observed only when it is in an X-ray quiescent state; 3.) it is intrinsically weak because it simply lacks an X-ray emitting region.

Keywords

Cite

@article{arxiv.astro-ph/0103026,
  title  = {The First Observations of the Second Brightest Quasar},
  author = {K. M. Leighly and J. P. Halpern and D. J. Helfand and R. H. Becker and C. D. Impey},
  journal= {arXiv preprint arXiv:astro-ph/0103026},
  year   = {2009}
}

Comments

15 pages including 5 figures; accepted for publication in the AJ (June 2001)