Where are Compton-thick radio galaxies? A hard X-ray view of three candidates

Abstract

We present a broad-band X-ray spectral analysis of the radio-loud active galactic nuclei NGC 612, 4C 73.08 and 3C 452, exploiting archival data from NuSTAR, XMM-Newton, Swift and INTEGRAL. These Compton-thick candidates are the most absorbed sources among the hard X-ray selected radio galaxies studied in Panessa et al. (2016). We find an X-ray absorbing column density in every case below $1.5\times 10^{24}$ cm${}^{-2}$, and no evidence for a strong reflection continuum or iron K $\alpha$ line. Therefore, none of these sources is properly Compton-thick. We review other Compton-thick radio galaxies reported in the literature, arguing that we currently lack strong evidences for heavily absorbed radio-loud AGNs.

Accepted for publication in MNRAS, 10 pages, 5 figures

References in corpus (22)

• The synthesis of the cosmic X-ray background in the Chandra and XMM-Newton era
• On the X-ray, optical emission line and black hole mass properties of local Seyfert galaxies
• The X-ray nuclei of intermediate-redshift radio sources
• On the origin of soft X-rays in obscured AGN: answers from high-resolution spectroscopy with XMM-Newton
• Suzaku Observations of Active Galactic Nuclei Detected in the Swift/BAT Survey: Discovery of "New Type" of Buried Supermassive Black Holes
• IACHEC Cross-Calibration of Chandra, NuSTAR, Swift, Suzaku, and XMM-Newton with 3C 273 and PKS 2155-304
• The NuSTAR View of Nearby Compton-thick AGN: The Cases of NGC 424, NGC 1320 and IC 2560
• Compton thick active galactic nuclei in Chandra surveys
• The HI absorption "Zoo"
• Compton Thick AGN in the XMM-COSMOS survey
• The properties of the young stellar populations in powerful radio galaxies at low and intermediate redshifts
• The NuSTAR Serendipitous Survey: The 40 month Catalog and the Properties of the Distant High Energy X-ray Source Population
• NuSTAR Reveals the Comptonizing Corona of the Broad-Line Radio Galaxy 3C 382
• Survival of the obscuring torus in the most powerful active galactic nuclei
• A Radio Through X-ray Study of the Jet/Companion-Galaxy Interaction in 3C 321
• Enormous disc of cool gas surrounding the nearby powerful radio galaxy NGC 612 (PKS 0131-36)
• Delving Into X-ray Obscuration of Type 2 AGN, Near and Far
• HST NIR Snapshot Survey of 3CR Radio Source Counterparts II: An Atlas and Inventory of the Host Galaxies, Mergers and Companions
• Connecting X-ray absorption and 21cm neutral hydrogen absorption in obscured radio AGN
• HI absorption in nearby compact radio galaxies
• Searching for highly obscured AGN in the XMM-Newton serendipitous source catalog
• Associated 21-cm HI absorption towards the radio galaxy 3C452 (J2245+3941)

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• NuSTAR Survey of Obscured Swift/BAT-selected Active Galactic Nuclei: II. Median High-energy Cutoff in Seyfert II Hard X-ray Spectra
• Observations of a radio-bright, X-ray obscured GRS 1915+105
• NuSTAR hard X-ray spectra of radio galaxies
• X-ray absorption in INTEGRAL AGN: Host galaxy inclination
• Compton-thick AGN in the NuSTAR era IV: A deep NuSTAR and XMM-Newton view of the candidate Compton thick AGN in ESO 116-G018
• INTEGRAL view of AGN
• Compton-thick AGN in the NuSTAR Era. IX. A Joint NuSTAR and XMM-Newton Analysis of Four Local AGN
• Observational hints on the torus obscuring gas behaviour through X-rays with NuSTAR data
• Cosmological 21cm line observations to test scenarios of super-Eddington accretion on to black holes being seeds of high-redshifted supermassive black holes
• Hard X-ray Irradiation Potentially Drives Negative AGN Feedback by Altering Molecular Gas Properties
• Reconciling X-ray and 21cm HI absorption gas column densities toward obscured AGN
• The Complex X-ray Obscuration Environment in the Radio Loud Type 2 Quasar 3C 223
• Broadband X-ray Spectral Study of Nuclear Structure in Local Obscured Radio Galaxies
• A broadband X-ray study of a sample of AGNs with [OIII] measured inclinations