A hard look at NGC 5347: revealing a nearby Compton-thick AGN

Abstract

Current measurements show that the observed fraction of Compton-thick (CT) AGN is smaller than the expected values needed to explain the cosmic X-ray background. Prior fits to the X-ray spectrum of the nearby Seyfert-2 galaxy NGC 5347 ($z=0.00792,D=35.5\mathrm{Mpc}$) have alternately suggested a CT and Compton-thin source. Combining archival data from $Suzaku$, $Chandra$, and - most importantly - new data from $NuSTAR$, and using three distinct families of models, we show that NGC 5347 is an obscured CTAGN ($N_{\mathrm{H}}>2.23\times 10^{24}\mathrm{c}{\mathrm{m}}^{-2}$). Its 2-30~keV spectrum is dominated by reprocessed emission from distant material, characterized by a strong Fe K$\alpha$ line and a Compton hump. We found a large equivalent width of the Fe K$\alpha$ line ($\mathrm{EW}=2.3\pm 0.3$ keV) and a high intrinsic-to-observed flux ratio ($\sim 100$). All of these observations are typical for bona fide CTAGN. We estimate a bolometric luminosity of $L_{\mathrm{bol}}\simeq 0.014\pm 0.005L_{Edd.}$. The $Chandra$ image of NGC 5347 reveals the presence of extended emission dominating the soft X-ray spectrum ($E<2\mathrm{keV}$), which coincides with the [O III] emission detected in the $HubbleSpaceTelescope$ images. Comparison to other CTAGN suggests that NGC 5347 is broadly consistent with the average properties of this source class. We simulated $XRISM$ and $Athena$/X-IFU spectra of the source, showing the potential of these future missions in identifying CTAGN in the soft X-rays.

Accepted for publication in ApJ

References in corpus (15)

• The Host Galaxies and Classification of Active Galactic Nuclei
• A Catalog of Quasar Properties from SDSS DR7
• Toward the Standard Population Synthesis Model of the X-Ray Background: Evolution of X-Ray Luminosity and Absorption Functions of Active Galactic Nuclei Including Compton-Thick Populations
• An XMM-Newton survey of broad iron lines in Seyfert galaxies
• BAT AGN Spectroscopic Survey I: Spectral Measurements, Derived Quantities, and AGN Demographics
• Occultation measurement of the size of the X-ray emitting region in the Active Galactic Nucleus of NGC 1365
• New Indicators for AGN Power: The Correlation Between [O IV] lambda 25.89 micron and Hard X-ray Luminosity for Nearby Seyfert Galaxies
• AGN dust tori at low and high luminosities
• A New Catalogue of Type 1 AGN and its Implication on the AGN Unified Model
• The NuSTAR View of Nearby Compton-thick AGN: The Cases of NGC 424, NGC 1320 and IC 2560
• The X-shooter Spectral Library (XSL): I. DR1. Near-ultraviolet through optical spectra from the first year of the survey
• Prevalence of High X-ray Obscuring Columns among AGN that Host H${}_2$O Masers
• Resolving the AGN and host emission in the mid-infrared using a model-independent spectral decomposition
• NuSTAR Resolves the First Dual AGN above 10 keV in SWIFT J2028.5+2543
• Orientation effects on spectral emission features of quasars

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