Faint AGNs at z>4 in the CANDELS GOODS-S field: looking for contributors to the reionization of the Universe

Abstract

In order to derive the AGN contribution to the cosmological ionizing emissivity we have selected faint AGN candidates at $z>4$ in the CANDELS GOODS-South field which is one of the deepest fields with extensive multiwavelength coverage from Chandra, HST, Spitzer and various groundbased telescopes. We have adopted a relatively novel criterion. As a first step high redshift galaxies are selected in the NIR $H$ band down to very faint levels ($H\le 27$) using reliable photometric redshifts. This corresponds at $z>4$ to a selection criterion based on the galaxy rest-frame UV flux. AGN candidates are then picked up from this parent sample if they show X-ray fluxes above a threshold of $F_X\sim 1.5\times 10^{-17}$ cgs (0.5-2 keV). We have found 22 AGN candidates at $z>4$ and we have derived the first estimate of the UV luminosity function in the redshift interval $4<z<6.5$ and absolute magnitude interval $-22.5\lesssim M_{1450}\lesssim -18.5$ typical of local Seyfert galaxies. The faint end of the derived luminosity function is about two/four magnitudes fainter at $z\sim 4-6$ than that derived from previous UV surveys. We have then estimated ionizing emissivities and hydrogen photoionization rates in the same redshift interval under reasonable assumptions and after discussion of possible caveats, the most important being the large uncertainties involved in the estimate of photometric redshift for sources with featureless, almost power-law SEDs and/or low average escape fraction of ionizing photons from the AGN host galaxies. We argue that, under reasonable evaluations of possible biases, the probed AGN population can produce at $z=4-6.5$ photoionization rates consistent with that required to keep highly ionized the intergalactic medium observed in the Lyman-$\alpha$ forest of high redshift QSO spectra, providing an important contribution to the cosmic reionization.

arXiv comment15 pages, 8 figures, A&A accepted, updated figure 6, corrected typo in table 3, updated references

References in corpus (76)

• Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Parameter Results
• CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey
• CANDELS: The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey - The Hubble Space Telescope Observations, Imaging Data Products and Mosaics
• Composite Quasar Spectra From the Sloan Digital Sky Survey
• Radiative Transfer in a Clumpy Universe: II. The Utraviolet Extragalactic Background
• Constraining the Evolution of the Ionizing Background and the Epoch of Reionization with z ~ 6 Quasars II: A Sample of 19 Quasars
• Radiative transfer in a clumpy universe: IV. New synthesis models of the cosmic UV/X-ray background
• Massive Molecular Outflows and Evidence for AGN Feedback from CO Observations
• The Evolution of the Galaxy Rest-Frame Ultraviolet Luminosity Function Over the First Two Billion Years
• The Chandra Deep Field-South Survey: 4 Ms Source Catalogs
• The Rest-Frame Extreme Ultraviolet Spectral Properties of QSOs
• New Constraints on Cosmic Reionization from the 2012 Hubble Ultra Deep Field Campaign
• CANDELS Multi-wavelength Catalogs: Source Detection and Photometry in the GOODS-South Field
• Reionization of the Inhomogeneous Universe
• The Birth of a Galaxy - III. Propelling reionisation with the faintest galaxies
• Absorption Properties and Evolution of Active Galactic Nuclei
• A Critical Assessment of Photometric Redshift Methods: A CANDELS Investigation
• The Great Observatories Origins Deep Survey. VLT/FORS2 Spectroscopy in the GOODS-South Field: Part III
• The incidence of obscuration in active galactic nuclei
• New Measurements of the Ionizing Ultraviolet Background over 2 < z < 5 and Implications for Hydrogen Reionization
• The Formation and Evolution of Massive Black Holes
• The galaxy stellar mass function at 3.5<z<7.5 in the CANDELS/UDS, GOODS-South, and HUDF fields
• Spectroscopic confirmation of z~7 LBGs: probing the earliest galaxies and the epoch of reionization
• The Great Observatories Origins Deep Survey - VLT/VIMOS Spectroscopy in the GOODS-South Field: Part II
• The impact of nebular emission on the ages of z~6 galaxies
• New observations of z~7 galaxies: evidence for a patchy reionization
• The Chandra Deep Field-South Survey: 2 Ms Source Catalogs
• Evolution of the Intergalactic Opacity: Implications for the Ionizing Background, Cosmic Star Formation, and Quasar Activity
• A measurement of secondary cosmic microwave background anisotropies from the 2500-square-degree SPT-SZ survey
• The Evolution of Lyman Limit Absorption Systems to Redshift Six
• CANDELS: The Contribution of the Observed Galaxy Population to Cosmic Reionization
• The Lyman-alpha forest opacity and the metagalactic hydrogen ionization rate at z~2-4
• The Blast Wave Model for AGN Feedback: Effects on AGN Obscuration
• The Giant Gemini GMOS survey of z>4.4 quasars - I. Measuring the mean free path across cosmic time
• The case for super-critical accretion onto massive black holes at high redshift
• The changing Lya optical depth in the range 6<z<9 from MOSFIRE spectroscopy of Y-dropouts
• Rapid Decline of Lyman-alpha Emission Toward the Reionization Era
• Measurements of the UV background at 4.6 < z < 6.4 using the quasar proximity effect
• Hubble Frontier Fields First Complete Cluster Data: Faint Galaxies at $z\sim 5-10$ for UV Luminosity Functions and Cosmic Reionization
• Faint high-redshift AGN in the Chandra Deep Field South: the evolution of the AGN luminosity function and black hole demography
• CANDELS/GOODS-S, CDFS, ECDFS: Photometric Redshifts For Normal and for X-Ray-Detected Galaxies
• HST-COS Observations of AGN. I. Ultraviolet Composite Spectra of the Ionizing Continuum and Emission Lines
• On The Detection Of Ionizing Radiation Arising From Star-Forming Galaxies At Redshift z ~ 3-4 : Looking For Analogs Of "Stellar Reionizers"
• A Direct Measurement of the IGM Opacity to HI Ionizing Photons
• The Faint End of the Quasar Luminosity Function at z~4: Implications for Ionization of the Intergalactic Medium and Cosmic Downsizing
• HST-COS Observations of AGN. II. Extended Survey of Ultraviolet Composite Spectra from 159 Active Galactic Nuclei
• Near-zone sizes and the rest frame extreme ultra-violet spectral index of the highest redshift quasars
• Narrowband imaging of Escaping Lyman-Continuum Emission in the SSA22 Field
• The Fall of the Quasar Population
• Evolution of the Quasar Luminosity Function Over 3 < z < 5 in the COSMOS Survey Field
• The photoheating of the intergalactic medium in synthesis models of the UV background
• The Subaru high-z quasar survey: discovery of faint z~6 quasars
• Escape Fraction of Ionizing Radiation from Starburst Galaxies at High Redshifts
• Bimodal Color Distribution in Hierarchical Galaxy Formation
• Intracluster and Intragroup Entropy from Quasar Activity
• The Hard X-Ray Luminosity Function of High-Redshift ($3<z\lesssim 5$) Active Galactic Nuclei
• The H I opacity of the intergalactic medium at redshifts 1.6 < z < 3.2
• Starburst Intensity Limit of Galaxies at z~5-6
• The Population of High Redshift AGNs in the Chandra COSMOS survey
• Narrowband Lyman-Continuum Imaging of Galaxies at z ~ 2.85
• AGN Feedback on the Intracluster Medium
• The systematic search for $z\gtrsim 5$ active galactic nuclei in the $Chandra$ Deep Field South
• A low escape fraction of ionizing photons of L>L* Lyman break galaxies at z=3.3
• Faint AGN and the Ionizing Background
• ALMA reveals a warm and compact starburst around a heavily obscured supermassive black hole at z=4.75
• Contamination on Lyman continuum emission at z >= 3: implication on the ionising radiation evolution
• Photo-heating and the fate of hard photons during the reionisation of HeII by quasars
• On the Evolution of the Cosmic Ionizing Background
• On the faint end of the high redshift AGN luminosity function
• The high-redshift (z>3) AGN population in the 4 Ms Chandra Deep Field South
• Spectroscopic Confirmation of Faint Lyman Break Galaxies at Redshifts Four and Five in the Hubble Ultra Deep Field
• AGN-driven helium reionization and the incidence of extended HeIII regions at redshift z>3
• AGNs as main contributors to the UV ionizing emissivity at high redshifts: predictions from a Lambda-CDM model with linked AGN/galaxy evolution
• Ultra-faint high-redshift galaxies in the Frontier Fields
• The red and blue galaxy populations in the GOODS field: evidence for an excess of red dwarfs
• The Evolution of Active Galactic Nuclei in Warm Dark Matter Cosmology

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• Cosmic Dawn II (CoDa II): a new radiation-hydrodynamics simulation of the self-consistent coupling of galaxy formation and reionization
• Mocking Faint Black Holes during Reionization
• New simulation of QSO X-ray heating during the Cosmic Dawn
• Measuring photo-ionization rate and mean free path of HeII ionizing photons at $2.5\le z\le 3.6$: Evidence for late and rapid HeII reionization Part-II
• Magnetic Reconnection as a Potential Driver of X-ray Variability in Active Galactic Nuclei
• An Overview of Mobile Capacitive Touch Technologies Trends
• The impact of black hole feedback on the UV luminosity and stellar mass assembly of high-redshift galaxies
• The Contribution of AGN Accretion Disks to Hydrogen Reionization
• Black Hole merger rates in the first billion years in light of JWST data
• Detecting the signature of helium reionization through 3HeII 3.46cm line-intensity mapping
• BASS XXX: Distribution Functions of DR2 Eddington-ratios, Black Hole Masses, and X-ray Luminosities
• Thermomagnetic Ettingshausen-Nernst effect in tachocline, magnetic reconnection phenomenon in lower layers, axion mechanism of solar luminosity variations, coronal heating problem solution and mechanism of ADM variations around BH
• Modelling intergalactic low ionisation metal absorption line systems near the epoch of reionization