A Fresh Look at AGN Spectral Energy Distribution Fitting with the XMM-SERVS AGN Sample

Abstract

We perform spectral energy distribution (SED) fitting to 711 luminous X-ray AGN at 0.7 < z < 4.5 using 10-bands of optical and infra-red photometric data for objects within XMM-SERVS. This fitting provided 510 reliable (reduced ${\chi }^2<3$) inferences on AGN and host galaxy properties. The AGN optical (3000Å) luminosity inferred from SED-fitting is found to correlate with the measured X-ray (2-10 keV) luminosity, in good agreement with previous work. Using X-ray hardness as a proxy for AGN obscuration, we also study the differences in the host galaxy properties of obscured and unobscured AGN. Both populations have consistent stellar masses (log${}_{10}(M_{\ast }/M_{\odot })$ = 10.88 $\pm 0.09M_{\odot }$ and log${}_{10}(M_{\ast }/M_{\odot })$ = 10.8 $\pm 0.1M_{\odot }$ for unobscured and obscured AGN respectively). We also find evidence for varying AGN emission line properties from a standard AGN template in 18.8% of the sample with a reduced ${\chi }^2<3$ where the inclusion of an additional emission line strength free parameter was found to improve the quality of the fit. Comparison of these fits to SDSS spectra showed that emission line properties inferred from broadband photometry were consistent with the results from spectroscopy for 91% of objects. We find that the presence of weaker, more blueshifted emission lines as inferred from the SED fits are associated with more negative values of ${\alpha }_{ox}$. While the correlation between the hardness of the ionising SED and the emission line properties has been known for some time, we are able to derive this correlation purely from broadband photometry.

arXiv comment13 pages, 8 figures. Accepted for publication by MNRAS

References in corpus (52)

• emcee: The MCMC Hammer
• Galactic Stellar and Substellar Initial Mass Function
• The Dust Content and Opacity of Actively Star-Forming Galaxies
• The Demography of Massive Dark Objects in Galaxy Centres
• The many lives of active galactic nuclei: cooling flows, black holes and the luminosities and colours of galaxies
• LSST: from Science Drivers to Reference Design and Anticipated Data Products
• Herschel Space Observatory - An ESA facility for far-infrared and submillimetre astronomy
• Observational Evidence of AGN Feedback
• The propagation of uncertainties in stellar population synthesis modeling I: The relevance of uncertain aspects of stellar evolution and the IMF to the derived physical properties of galaxies
• Local Supermassive Black Holes, Relics of Active Galactic Nuclei and the X-ray Background
• CIGALE: a python Code Investigating GALaxy Emission
• Spectral Energy Distributions and Multiwavelength Selection of Type 1 Quasars
• The propagation of uncertainties in stellar population synthesis modeling III: model calibration, comparison, and evaluation
• The Hyper Suprime-Cam SSP Survey: Overview and Survey Design
• Spectral Energy Distributions of Hard X-ray selected AGNs in the XMDS Survey
• SWIRE: The SIRTF Wide-area InfraRed Extragalactic Survey
• Stellar Population Inference with Prospector
• The Illustris simulation: the evolving population of black holes across cosmic time
• Revisiting the Infrared Spectra of Active Galactic Nuclei with a New Torus Emission Model
• The Sloan Digital Sky Survey Quasar Catalog: Sixteenth Data Release
• Second Data Release of the Hyper Suprime-Cam Subaru Strategic Program
• The dust covering factor in active galactic nuclei
• Unification of Luminous Type 1 Quasars through CIV Emission
• The Dust Attenuation Law in Distant Galaxies: Evidence for Variation with Spectral Type
• Absorption Properties and Evolution of Active Galactic Nuclei
• On the cosmic evolution of the scaling relations between black holes and their host galaxies: Broad Line AGN in the zCOSMOS survey
• The VISTA Deep Extragalactic Observations (VIDEO) Survey
• Fitting the integrated Spectral Energy Distributions of Galaxies
• The Dark Energy Survey Data Release 2
• Evidence for Ubiquitous, High-EW Nebular Emission in z~7 Galaxies: Towards a Clean Measurement of the Specific Star Formation Rate using a Sample of Bright, Magnified Galaxies
• The impact of nebular emission on the ages of z~6 galaxies
• Accreting SMBHs in the COSMOS field and the connection to their host galaxies
• Constraining the properties of AGN host galaxies with Spectral Energy Distribution modeling
• A lack of evolution in the very bright-end of the galaxy luminosity function from z = 8-10
• How Well Can We Measure the Stellar Mass of a Galaxy: The Impact of the Assumed Star Formation History Model in SED Fitting
• AGNfitter: A Bayesian MCMC approach to fitting spectral energy distributions of AGN
• The XMM-SERVS survey: new XMM-Newton point-source catalog for the XMM-LSS field
• AGN vs. host galaxy properties in the COSMOS field
• Dynamical Versus Stellar Masses in Compact Early-Type Galaxies: Further Evidence for Systematic Variation in the Stellar Initial Mass Function
• The Host-Galaxy Properties of Type 1 Versus Type 2 Active Galactic Nuclei
• Modelling type 1 quasar colours in the era of Rubin and Euclid
• Multi-wavelength properties of Type 1 and Type 2 AGN Host Galaxies in the Chandra-COSMOS Legacy Survey
• The X-ray emission of z>2.5 active galactic nuclei can be obscured by their host galaxies
• The correlations between optical/UV broad lines and X-ray emission for a large sample of quasars
• Deep Extragalactic VIsible Legacy Survey (DEVILS): Identification of AGN through SED Fitting and the Evolution of the Bolometric AGN Luminosity Function
• Galaxy properties of type 1 and 2 X-ray selected AGN and comparison among different classification criteria
• An obscured AGN population hidden in the VIPERS galaxies: identification through spectral energy distribution decomposition
• Physical Properties of Luminous Dust Poor Quasars
• Modelling the M*-SFR relation at high redshift: untangling factors driving biases in the intrinsic scatter measurement
• 4MOST Consortium Survey 6: Active Galactic Nuclei
• The role of galaxy mass on AGN emission: a view from the VANDELS survey
• MAGPHYS: a publicly available tool to interpret observed galaxy SEDs