SPACE DENSITY OF OPTICALLY SELECTED TYPE 2 QUASARS

By R. Reyes, N. Zakamska, M. Strauss, J. Green, Julian Krolik, Yue Shen, Gordon Richards, S. Anderson, D. Schneider. 2008

241 citations recorded by the source corpus.

Type 2 quasars are luminous active galactic nuclei whose central regions are obscured by large amounts of gas and dust. In this paper, we present a catalog of type 2 quasars from the Sloan Digital Sky Survey, selected based on their optical emission lines. The catalog contains 887 objects with redshifts z < 0.83; this is 6 times larger than the previous version and is by far the largest sample of type 2 quasars in the literature. We derive the [O iii]5007 luminosity function (LF) for 108.3 L☉ < L[O iii] < 1010 L☉ (corresponding to intrinsic luminosities up to M[2500 Å] ≃ −28 mag or bolometric luminosities up to 4 × 1047 erg s−1). This LF provides robust lower limits to the actual space density of obscured quasars due to our selection criteria, the details of the spectroscopic target selection, and other effects. We derive the equivalent LF for the complete sample of type 1 (unobscured) quasars and determine the ratio of type 2 to type 1 quasar number densities. Our data constrain this ratio to be at least ∼1.5:1 for 108.3 L☉ < L[O iii] < 109.5 L☉ at z < 0.3, and at least ∼1.2:1 for L[O iii] ∼ 1010 L☉ at 0.3 < z < 0.83. Type 2 quasars are at least as abundant as type 1 quasars in the relatively nearby universe (z ≲ 0.8) for the highest luminosities.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/909cf282a2e13f3be7f9377505ea99d2c79d3acd

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

In Instrumentation

Citations in the corpus

Observations of feedback from radio-quiet quasars – II. Kinematics of ionized gas nebulae (2013, methodology): “The sample presented in this paper consists of 11 radio-quiet obscured quasars at z ∼ 0.5 selected to be among the most [O III] λ5007-luminous objects in the catalogue by Reyes et al. (2008).”
THE SDSS-III BARYON OSCILLATION SPECTROSCOPIC SURVEY: THE QUASAR LUMINOSITY FUNCTION FROM DATA RELEASE NINE (2012, unknown): “…Croom et al. 2004; Hao et al. 2005; Richards et al. 2005, 2006b; Fan et al. 2006; Jiang et al. 2006; Fontanot et al. 2007; Bongiorno et al. 2007; Reyes et al. 2008; Jiang et al. 2008, 2009; Croom et al. 2009a; Glikman et al. 2010; Willott et al. 2010; Glikman et al. 2011; Ikeda et al. 2011,…”
A CATALOG OF QUASAR PROPERTIES FROM SLOAN DIGITAL SKY SURVEY DATA RELEASE 7 (2010, methodology): “This correlation is usually used to estimate the bolometric luminosity using the [OIII] λ5007 luminosity as a surrogate for type 2 quasars (e.g, Kauffmann et al. 2003; Zakamska et al. 2003; Heckman et al. 2004; Reyes et al. 2008).”
SPECTRAL CLASSIFICATION AND REDSHIFT MEASUREMENT FOR THE SDSS-III BARYON OSCILLATION SPECTROSCOPIC SURVEY (2012, methodology): “We augment these data with a sample of 28 type-II quasars (e.g., Zakamska et al. 2003; Reyes et al. 2008) identified within the BOSS spectroscopic data set (see the discussion in §6).”
Active galactic nuclei: what’s in a name? (2017, background): “The irony is that a large fraction of known type 2 AGN are still selected in the optical (Zakamska et al. 2003; Reyes et al. 2008; Alexandroff et al. 2013; Yuan et al. 2016).”
The Sloan Digital Sky Survey Quasar Catalog: Fourteenth data release (2017, background): “…et al. 2006; Jiang et al. 2008), large samples of broad absorption line (BAL) quasars (e.g. Reichard et al. 2003; Trump et al. 2006; Gibson et al. 2008), type 2 candidates (Reyes et al. 2008) or samples of objects with peculiar properties such as weak emission lines (Diamond-Stanic et al. 2009).”
Discovery of extreme [O III] λ5007 Å outflows in high-redshift red quasars (2015, background): “For this reason, Zakamska et al. (2003), Reyes et al. (2008) and Alexandroff et al. (2013) expanded the search for type 2 quasars to FWHM(Hβ) ≤ 2000 km s−1.”
Quasar feedback and the origin of radio emission in radio-quiet quasars (2014, methodology): “Our estimate of the number density of these objects suggests that they are at least as common as unobscured quasars at the same redshifts and line luminosities (Reyes et al. 2008).”
What drives the growth of black holes (2011, background): “…Page et al., 2004; Comastri et al., 2011), detection of luminous, narrow emission lines (e.g., Zakamska et al., 2003; Alexander et al., 2008b; Reyes et al., 2008; Vignali et al., 2010; Gilli et al., 2010; Juneau et al., 2011), or through optical-to-mid-IR SEDs (e.g., Hickox et al., 2007;…”
Revisiting the Unified Model of Active Galactic Nuclei (2015, methodology): “An alternative method to detect luminous type-II AGNs up to z ∼ 0.83 (Reyes et al. 2008, and refferences therein) is to search for strong [O iii] lines relative to Hβ which is required not to show a broad component.”
Observations of feedback from radio-quiet quasars - I. Extents and morphologies of ionized gas nebulae (2013, methodology): “Among other findings, at the highest luminosities, it has become clear that these objects constitute at least half of the quasar population (Reyes et al. 2008) and are therefore representative of “typical” black hole activity.”
THE RADIATIVE EFFICIENCY OF ACCRETION FLOWS IN INDIVIDUAL ACTIVE GALACTIC NUCLEI (2010, background): “60◦ at the higher luminosities characteristic of our sample (Polletta et al. 2008; Reyes et al. 2008).”
Kiloparsec-scale outflows are prevalent among luminous AGN: outflows and feedback in the context of the overall AGN population (2014, background): “J1010+0612 Reyes et al. (2008) previously identified J1010+0612 as a type 2 (“obscured”) quasar.”
FEEDBACK IN LUMINOUS OBSCURED QUASARS (2011, methodology): “The sample, withz< 0.8, was selected based on the [OIII ] line luminosity (Zakamska et al. 2003) and now comprises nearly 1000 objects (Reyes et al. 2008).”