The Discovery of a Luminous z = 5.80 Quasar from the Sloan Digital Sky Survey

By Xiaohui Fan, R. White, M. Davis, Robert H. Becker, M. Strauss, Zoltán Haiman, D. Schneider, M. Gregg, James E. Gunn, G. Knapp and 32 more. 2000

248 citations recorded by the source corpus.

We present observations of SDSSp J104433.04-012502.2, a luminous quasar at z = 5.80 discovered from Sloan Digital Sky Survey (SDSS) multicolor imaging data. This object was selected as an i′-band dropout object, with i* = 21.8 ± 0.2 and z* = 19.2 ± 0.1. It has an absolute magnitude M1450 = -27.2 (H0 = 50 km s-1 Mpc-1, q0 = 0.5). The spectrum shows a strong and broad Lyα emission line, strong Lyα forest absorption lines with a mean continuum decrement DA = 0.91 and a Lyman limit system at z = 5.72. The spectrum also shows strong O I and Si IV emission lines similar to those of quasars at z ≲ 5, suggesting that these metals were produced at a redshift beyond 6. The lack of a Gunn-Peterson trough in the spectrum indicates that the universe is already highly ionized at z ∼ 5.8. Using a high-resolution spectrum in the Lyα forest region, we place a conservative upper limit on the optical depth because of the Gunn-Peterson effect of τ < 0.5 in regions of minimum absorption. The Lyα forest absorption in this object is much stronger than that in quasars at z ≲ 5. The object is unresolved in a deep image with excellent seeing, implying that it is unlensed. The black hole mass of this quasar is ∼3 × 109 M⊙ if we assume no lensing amplification and that it is radiating at the Eddington luminosity, implying that it resides in a very massive dark matter halo. The discovery of one quasar at M1450 < -27 in a survey area of 600 deg2 is consistent with an extrapolation of the observed luminosity function at lower redshifts. The abundance and evolution of such quasars can provide sensitive tests for models of quasar and galaxy formation.

Subfields: Astronomy and Astrophysics

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Citations in the corpus

Simulations of Pregalactic Structure Formation with Radiative Feedback (2000, background): “The observation of quasars at redshifts as high as z = 5.8 (Fan et al. 2000) with no accompanying GunnPeterson absorption trough in their spectra indicates that the onset of reionization occurs quite early (z ≥ 7) and so the first generation of stars forms even earlier.”
The Minimum Universal Metal Density between Redshifts of 1.5 and 5.5 (2001, methodology): “This paper analyses the distribution of C IV and Si IV ions in the IGM over a wide range of redshifts from z = 1.5 to z = 5.5 using newly-discovered Sloan Digital Sky Survey (SDSS) quasars (Anderson et al. 2001; Fan et al. 1999, 2000a,b, 2001a,b; Zheng et al. 2000) to provide a high redshift sample.”
The Chandra Deep Field North Survey. VI. The Nature of the Optically Faint X-Ray Source Population (2001, unknown): “04–012502.2 which lies at z = 5.8 (Fan et al. 2000) and hasi′ − K = 4.8.”
EVIDENCE FOR NON-EVOLVING Fe ii/Mg ii RATIOS IN RAPIDLY ACCRETING z ∼ 6 QSOs (2011, background): “In the past 10 years, more than 50 QSOs at z > 5.7 have been discovered (Fan et al. 2000, 2001, 2003, 2004, 2006; Jiang et al. 2008, 2009; Willott et al. 2007, 2010) thanks to the Sloan Digital Sky Survey (SDSS, York et al. 2000) and other large multi-wavelength surveys such as the Canada France…”
What Is the Highest Plausible Redshift of Luminous Quasars? (2000, background): “Approximately 200 quasars have been found so far at z[ 4 (the majority of which were discovered from follow-ups of Palomar Sky Survey digital scans),2 including the recordholding bright quasar SDSS 1044[0125 at z\ 5.80, recently discovered by the Sloan Digital Sky Survey (SDSS; Fan et al. 2000).”
The physics of the intergalactic medium (2007, methodology): “…of the IGM measured in the spectra of several z > 5.8 QSOs discovered by the Sloan Digital Sky Survey has shown that the IGM was reionized by z ≃ 5.7 (Fan et al., 2001a, 2000), but the Lyα optical depth rises rapidly towards higher redshifts (Becker et al., 2007, 2001; Djorgovski et al., 2001;…”
The UKIRT Infrared Deep Sky Survey ZY JHK photometric system: passbands and synthetic colours (2006, background): “The general principle used to find high–redshift quasars 3 < z < 6.4 with broadband photometry (e.g. Warren, Hewett & Osmer, 1991; Fan et al. 2000b) is to image in three bands, one (a) blueward of redshifted Lyα, a second (b) containing or just redward of Lyα, and a third (c) further to the red.”
The effects of photoionization on galaxy formation – I. Model and results at z=0 (2001, background): “…high redshifts, as is predicted by current structure formation models (e.g. Benson et al. 2001a) and as confirmed up to redshifts ≈ 6 observationally (Fan et al. 2000; Stern et al. 2000), then reionization is most likely to have occurred through photoionization, as both galaxies and quasars emit…”
Intergalactic Magnetic Fields from Quasar Outflows (2001, background): “It is now known from observations of high-redshift quasars that the diffuse IGM was reionized at a redshift z ∼> 6 (Fan et al. 2000).”
A SURVEY OF z ∼ 6 QUASARS IN THE SLOAN DIGITAL SKY SURVEY DEEP STRIPE. I. A FLUX-LIMITED SAMPLE AT zAB < 21 (2007, background): “In recent years, over twenty z ∼ 6 quasars with zAB ≤ 20 have been discovered (e.g. Fan et al. 2000, 2001a, 2003, 2004, 2006a; Goto 2006).”
Photoevaporation of cosmological minihaloes during reionization (2003, background): “The absence of a Gunn–Peterson (GP) trough in the spectra of high-redshift quasars at observed wavelengths λα(1 + z) due to Lyα resonance scattering by hydrogen atoms in the IGM at z < 6 indicates that the IGM was very highly ionized at all z < 6 (Fan et al. 2000).”
The Sloan Digital Sky Survey: Technical Summary (2000, background): “Strauss et al. (1999), Schneider et al. (2000), Fan et al. (2000b), Tsvetanov et al. (2000), Pier et al. (2000) and Leggett et al. (2000) report the discovery of a number of very low mass stars or substellar objects, those of type ‘L’ or ‘T’, including the first field methane (‘T’) dwarfs and the…”
The Reionization of the Universe by the First Stars and Quasars (2000, background): “Current observations are at the threshold of probing this epoch of reionization, given the fact that galaxies and quasars at redshifts ∼ 6 are being discovered (Fan et al. 2000; Stern et al. 2000).”
Gemini Near-Infrared Spectroscopy of Luminous z ∼ 6 Quasars: Chemical Abundances, Black Hole Masses, and Mg II Absorption (2007, background): “SDSS J1044 0125 was the first quasar discovered at z > 5:7 (Fan et al. 2000).”
Reionization by Hard Photons. I. X-Rays from the First Star Clusters (2000, background): “8\ z r \ 35, lack of Gunn-Peterson absorption in the spectra of highredshift quasars (Fan et al. 2000), and the upper bound comes from the observation of small-scale power in cosmic microwave background (CMB) anistropies (Griffiths, Barbosa, & Liddle 1999).”