Cosmological Evolution of the Hard X-Ray Active Galactic Nucleus Luminosity Function and the Origin of the Hard X-Ray Background

By Y. Ueda, M. Akiyama, K. Ohta, T. Miyaji. 2003

915 citations recorded by the source corpus.

We investigate the cosmological evolution of the hard X-ray luminosity function (HXLF) of active galactic nuclei (AGNs) in the 2-10 keV luminosity range of 1041.5-1046.5 ergs s-1 as a function of redshift up to 3. From a combination of surveys conducted at photon energies above 2 keV with HEAO 1, ASCA, and Chandra, we construct a highly complete (>96%) sample consisting of 247 AGNs over the wide flux range of 10-10 to 3.8 × 10-15 ergs cm-2 s-1 (2-10 keV). For our purpose, we develop an extensive method of calculating the intrinsic (before absorption) HXLF and the absorption (NH) function. This utilizes the maximum likelihood method, fully correcting for observational biases with consideration of the X-ray spectrum of each source. We find that (1) the fraction of X-ray absorbed AGNs decreases with the intrinsic luminosity and (2) the evolution of the HXLF of all AGNs (including both type I and type II AGNs) is best described with a luminosity-dependent density evolution (LDDE) where the cutoff redshift increases with the luminosity. Our results directly constrain the evolution of AGNs that produce a major part of the hard X-ray background, thus solving its origin quantitatively. A combination of the HXLF and the NH function enables us to construct a purely "observation-based" population synthesis model. We present basic consequences of this model and discuss the contribution of Compton-thick AGNs to the rest of the hard X-ray background.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/70c3d26e826adab6a68163d380916a26fcf73e03

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 Nuclear and High Energy Physics

Citations in the corpus

The many manifestations of downsizing: hierarchical galaxy formation models confront observations (2009, neutral): “This trend is found both for X-ray (Ueda et al. 2003; Hasinger, Miyaji & Schmidt 2005) and for optically (Cristiani et al. 2004; Fontanot et al. 2007) selected AGN, but it strongly depends on the modelling of obscuration (e.g. La Franca et al. 2005).”
The 2dF-SDSS LRG and QSO Survey: the QSO luminosity function at 0.4 < z < 2.6 (2009, background): “They show that the activity in faint AGN peaks at a lower redshift than that of more luminous AGN (e.g. Ueda et al. 2003; Hasinger, Miyaji & Schmidt 2005); this process has been described as AGN downsizing (e.g. Barger et al. 2005).”
The incidence of obscuration in active galactic nuclei (2013, methodology): “…to corroborate claims of positive evolution of the fraction of obscured AGN with increasing redshift (La Franca et al. 2005; Ballantyne et al. 2006; Treister et al. 2006; Hasinger 2008) as well as counterclaims of no significant evolution (Ueda et al. 2003; Tozzi et al. 2006; Gilli et al. 2007).”
MASS FUNCTIONS OF THE ACTIVE BLACK HOLES IN DISTANT QUASARS FROM THE LARGE BRIGHT QUASAR SURVEY, THE BRIGHT QUASAR SURVEY, AND THE COLOR-SELECTED SAMPLE OF THE SDSS FALL EQUATORIAL STRIPE (2009, background): “By comparing the mass functions for individual mass bins the cosmic downsizing (e.g., Ueda et al. 2003) of active black holes is clearly evident: the most massive black holes are the most active at high redshifts while the lowest mass black holes are the most active at low redshift.”
BAT AGN Spectroscopic Survey. V. X-Ray Properties of the Swift/BAT 70-month AGN Catalog (2017, background): “…of obscured and unobscured AGN (e.g., Della Ceca et al. 2008; Burlon et al. 2011; Aird et al. 2015), and is consistent with the observed decrease of the fraction of obscured sources with increasing luminosity (e.g., Ueda et al. 2003; Treister & Urry 2006; Burlon et al. 2011; Ueda et al. 2014).”
Evidence for Quasar Activity Triggered by Galaxy Mergers in HST Observations of Dust-reddened Quasars (2007, background): “%) of the accretion process in AGNs is obscured and only themost energetic photons (>20 keV) can penetrate the obscuring dust barrier (Gilli et al. 2001, 2007; Ueda et al. 2003).”
THE LUMINOSITY FUNCTION OF FERMI-DETECTED FLAT-SPECTRUM RADIO QUASARS (2011, methodology): “The epoch of this “redshift peak” correlates with source luminosity (e.g., Ueda et al. 2003; Hasinger et al. 2005).”
Present-Day Growth of Black Holes and Bulges: The Sloan Digital Sky Survey Perspective (2004, background): “More recently X-ray surveys (Ueda et al. 2003; Steffen et al. 2003) have shown that the peak in the comoving emissivity of the AGN population occurs at lower and lower redshift for AGNs of lower and lower luminosity.”
Swift BAT Survey of AGNs (2007, result): “While this has been seen in several X-ray-selected surveys (Ueda et al. 2003; La Franca et al. 2005; Shinozaki et al. 2006), the fact that the selection of BATsources is independent of the line-of-sight column density confirms and extends these results.”
THE NUCLEAR SPECTROSCOPIC TELESCOPE ARRAY (NuSTAR) HIGH-ENERGY X-RAY MISSION (2013, background): “…and luminosity correspond to the peak epoch in the black hole accretion history of the Universe and the knee of the X-ray luminosity function (e.g., Ueda et al. 2003; La Franca et al. 2005; Aird et al. 2010); thus, NuSTAR should detect the AGN source population that dominates the cosmic growth of…”
The MAXI Mission on the ISS: Science and Instruments for Monitoring All-Sky X-Ray Images (2009, background): “It is estimated that a confusion limit of X-ray sources is 5×10−12 erg cm−2 sec−1 from recent Log N - Log S plot of X-ray sources (Ueda et al. 2003); i.e., 0.2 mCrab in the energy band of 2 to 20 keV.”
The AKARI/IRC mid-infrared all-sky survey (2010, background): “The population of obscured AGNs is expected to contribute to the hard X-ray background, which is not competely resolved into individual sources yet Ueda et al. (2003).”
The unresolved hard X-ray background: the missing source population implied by the Chandra and XMM-Newton deep fields (2004, background): “…at low fluxes, suggest that there may be an as yet undetected population of highly obscured sources, such as the heavily absorbed AGN predicted in recent synthesis models (e.g. Gilli, Salvati & Hasinger 2001; Franceschini, Braito & Fadda 2002; Gandhi & Fabian 2003; Ueda et al. 2003; Comastri 2004).”
The XMM-Newton Wide-Field Survey in the COSMOS Field. I. Survey Description (2006, background): “…the number of highly obscured objects missing in the current deep X–ray samples is limited by the integrated constraints on the number counts, the hard X–ray and soft gamma–ray background (Ueda et al. 2003) and the mass function of supermassive black holes in local galaxies (Marconi et al. 2004).”
An Observational Determination of the Bolometric Quasar Luminosity Function (2006, methodology): “A reflection component is included following Ueda et al. (2003) generatedwith the PEXRAVmodel (Magdziarz & Zdziarski 1995) in the XSPEC package with a reflection solid angle of 2 , inclination cos i ¼ 0:5, and solar abundances.”
COMPTON-THICK ACCRETION IN THE LOCAL UNIVERSE (2015, methodology): “We follow the same analysis as in Ueda et al. (2003, 2014) to constrain the “NH function” f L z N, ;i i iX H[ ( )], which represents the probability distribution function of the line of sight column density of an AGN.”
Infrared Power-Law Galaxies in the Chandra Deep Field-South: Active Galactic Nuclei and Ultraluminous Infrared Galaxies (2006, methodology): “Ueda et al. (2003) derive a ratio of about 1:1 for hard X-ray detections of obscured (NH > 10 22 cm 2) to unobscured AGNs.”
The VISTA deep extragalactic observations (VIDEO) survey (2012, background): “…important to note that the epoch over which VIDEO is aimed is a crucial one in the history of the Universe, as this is when the bulk of the star formation (e.g. Madau et al. 1996; Hopkins & Beacom 2006; Lapi et al. 2011) and accretion (e.g. Ueda et al. 2003; Croom et al. 2009) activity took place.”
GOODS-Herschel: the far-infrared view of star formation in active galactic nucleus host galaxies since z ≈ 3 (2011, background): “Indeed, integrating the analytic AGN X-ray luminosity functions of Ueda et al. (2003) and assuming the luminosity-dependent bolometric correctionfactor of Marconi et al. (2004) reveals thatLX= 1042–1044 ergs s−1 AGNs have accounted for≈65 per cent of all black hole growth since z∼ 1.”