Discovery of the most luminous quasar of the last 9 Gyr - INSU - Institut national des sciences de l'Univers Access content directly
Journal Articles Publications of the Astronomical Society of Australia Year : 2022

Discovery of the most luminous quasar of the last 9 Gyr

Christopher A. Onken
  • Function : Author
Samuel Lai
  • Function : Author
Christian Wolf
  • Function : Author
Adrian B. Lucy
  • Function : Author
Wei Jeat Hon
  • Function : Author
Jennifer L. Sokoloski
  • Function : Author
Gerardo J. M. Luna
  • Function : Author
Xiaohui Fan
  • Function : Author
Fuyan Bian
  • Function : Author

Abstract

We report the discovery of a bright ( $g = 14.5$ mag (AB), $K = 11.9$ mag (Vega)) quasar at redshift $z=0.83$ — the optically brightest (unbeamed) quasar at $z>0.4$ . SMSS J114447.77-430859.3, at a Galactic latitude of $b=+18.1^{\circ}$ , was identified by its optical colours from the SkyMapper Southern Survey (SMSS) during a search for symbiotic binary stars. Optical and near-infrared spectroscopy reveals broad Mg II, H $\unicode{x03B2}$ , H $\unicode{x03B1}$ , and Pa $\unicode{x03B2}$ emission lines, from which we measure a black hole mass of $\log_{10}\! (M_{BH}/M_{\odot}) = 9.4 ± 0.5$ . With its high luminosity, $L_{bol} = (4.7±1.0)×10^{47} erg s^{-1}$ or $Mi(z=2) = -29.74$ mag (AB), we estimate an Eddington ratio of $≈1.4$ . As the most luminous quasar known over the last ${∼}$ 9 Gyr of cosmic history, having a luminosity $8×$ greater than 3C 273, the source offers a range of potential follow-up opportunities.

Dates and versions

insu-03839677 , version 1 (04-11-2022)

Identifiers

Cite

Christopher A. Onken, Samuel Lai, Christian Wolf, Adrian B. Lucy, Wei Jeat Hon, et al.. Discovery of the most luminous quasar of the last 9 Gyr. Publications of the Astronomical Society of Australia, 2022, 39, ⟨10.1017/pasa.2022.36⟩. ⟨insu-03839677⟩
18 View
0 Download

Altmetric

Share

Gmail Facebook X LinkedIn More