X-ray and infrared diagnostics of nearby active galactic nuclei with MAXI and AKARI

Abstract

Nearby active galactic nuclei were diagnosed in the X-ray and mid-to-far infrared wavelengths, with Monitor of All-sky X-ray Image (MAXI) and the Japanese infrared observatory AKARI, respectively. Among the X-ray sources listed in the second release of the MAXI all-sky X-ray source catalog, 100 ones are currently identified as a non-blazar-type active galactic nucleus. These include 95 Seyfert galaxies and 5 quasars, and they are composed of 73 type-1 and 27 type-2 objects. The AKARI all-sky survey point source catalog was searched for their mid- and far-infrared counterparts at 9, 18, and 90 $\mu$m. As a result, 69 Seyfert galaxies in the MAXI catalog (48 type-1 and 21 type-2 ones) were found to be detected with AKARI. The X-ray (3-4 keV and 4-10 keV) and infrared luminosities of these objects were investigated, together with their color information. Adopting the canonical photon index, $\Gamma =1.9$, of the intrinsic X-ray spectrum of the Seyfert galaxies, the X-ray hardness ratio between the 3-4 and 4-10 keV ranges derived with MAXI was roughly converted into the absorption column density. After the X-ray luminosity was corrected for absorption from the estimated column density, the well-known X-ray-to-infrared luminosity correlation was confirmed at least in the Compton-thin regime. In contrast, NGC 1365, only one Compton-thick object in the MAXI catalog, was found to deviate from the correlation toward a significantly lower X-ray luminosity by nearly an order of magnitude. It was verified that the relation between the X-ray hardness below 10 keV and X-ray-to-infrared color acts as an effective tool to pick up Compton-thick objects. The difference in the infrared colors between the type-1 and type-2 Seyfert galaxies and its physical implication on the classification and unification of active galactic nuclei were briefly discussed.

arXiv commentAccepted for PASJ, 10 figures, 3 tables

References in corpus (37)

• Unified Schemes for Radio-Loud Active Galactic Nuclei
• The synthesis of the cosmic X-ray background in the Chandra and XMM-Newton era
• The MAXI Mission on the ISS: Science and Instruments for Monitoring All Sky X-Ray Images
• The Infrared Astronomical Mission AKARI
• AGN Dusty Tori: II. Observational Implications of Clumpiness
• 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
• The AKARI/IRC Mid-Infrared All-Sky Survey
• The 70 Month Swift-BAT All-Sky Hard X-Ray Survey
• AGN Dusty Tori: I. Handling of Clumpy Media
• The MCXC: a Meta-Catalogue of X-ray detected Clusters of galaxies
• The Infrared Camera (IRC) for AKARI - Design and Imaging Performance
• Resolving the mid-infrared cores of local Seyferts
• Three years Swift-BAT Survey of AGN: reconciling theory and observations?
• The Far-Infrared Surveyor (FIS) for AKARI
• Extreme X-ray spectral variability in the Seyfert 2 Galaxy NGC 1365
• Occultation measurement of the size of the X-ray emitting region in the Active Galactic Nucleus of NGC 1365
• Dusty Structure Around Type-I Active Galactic Nuclei: Clumpy Torus Narrow Line Region and Near-Nucleus Hot Dust
• Gas Slit Camera (GSC) onboard MAXI on ISS
• Suzaku Observations of Active Galactic Nuclei Detected in the Swift/BAT Survey: Discovery of "New Type" of Buried Supermassive Black Holes
• In-Orbit Performance of MAXI Gas Slit Camera (GSC) on ISS
• The Toroidal Obscuration of Active Galactic Nuclei
• The XMM-Newton long look of NGC 1365: uncovering of the obscured X-ray source
• Mid and Far Infrared Properties of a Complete Sample of Local AGNs
• The Suzaku Observation of the Nucleus of the Radio-Loud Active Galaxy Centaurus A: Constraints on Abundances of the Accreting Material
• X-ray absorption, nuclear infrared emission and dust covering factors of AGN: testing Unification Schemes
• NuSTAR and XMM-Newton Observations of the Hard X-Ray Spectrum of Centaurus A
• A new technique to efficiently select Compton-thick AGN
• Infrared and hard X-ray diagnostics of AGN identification from the Swift/BAT and AKARI all-sky surveys
• MAXI investigation into the longterm X-ray variability from the very-high-energy gamma-ray blazar Mrk 421
• Bright X-ray flares from the BL Lac object Mrk 421, detected with MAXI in 2010 January and February
• Revisit of Local X-ray Luminosity Function of Active Galactic Nuclei with the MAXI Extragalactic Survey
• A strong excess in the 20-100 keV emission of NGC 1365
• The 37-month MAXI/GSC source catalog in the high Galactic-latitude sky
• The First MAXI/GSC Catalog in the High Galactic-Latitude Sky
• AKARI-CAS --- Online Service for AKARI All-Sky Catalogues
• A New Sample of Obscured AGNs Selected from the XMM-Newton and AKARI Surveys
• A Soft X-Ray Lag Detected in Centaurus A

Cited by in corpus (3)

• X-ray spectral analyses of AGNs from the 7Ms Chandra Deep Field-South survey: the distribution, variability, and evolution of AGN's obscuration
• Does the mid-infrared-hard X-ray luminosity relation for active galactic nuclei depend on Eddington ratio?
• The 7-year MAXI/GSC X-ray Source Catalog in the High Galactic-Latitude Sky (3MAXI)