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Date and Time of the Query: 2019-04-18 T13:23:26 PDT
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For refcode 2009A&A...502..457G:
Retrieve 42 NED objects in this reference.
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Copyright by European Southern Observatory (ESO). Reproduced by permission
2009A&A...502..457G Resolving the mid-infrared cores of local Seyferts Gandhi, P.; Horst, H.; Smette, A.; Honig, S.; Comastri, A.; Gilli, R.; Vignali, C.; Duschl, W. Abstract. We present new photometry of 16 local Seyferts including 6 Compton-thick sources in N-band filters around 12- micron, obtained with the VISIR instrument on the 8-m Very Large Telescope. The near-diffraction-limited imaging provides the least-contaminated core fluxes for these sources to date. Augmenting these with our previous observations and with published intrinsic X-ray fluxes, we form a total sample of 42 sources for which we find a strong mid-infrared:X-ray (12.3 micron:2-10 keV) luminosity correlation. Performing a physically-motivated subselection of sources in which the Seyfert torus is likely to be best-resolved results in the correlation L_MIR is proportional to L_X^1.11+/- 0.07^, with a reduction of the scatter in luminosities as compared to the full sample. Consideration of systematics suggests a range of 1.02-1.21 for the correlation slope. The mean 2-keV:12.3-micron spectral index ({alpha}_IX) is found to be -1.10 +/- 0.01, largely independent of luminosity. Indirectly-computed 12-micron bolometric corrections range over ~10-30 if a known luminosity trend of X-ray bolometric corrections is assumed. Comparison with ISO data spanning a wider luminosity range suggests that our correlation can be extended into the quasar regime. That unobscured, obscured, and Compton-thick sources all closely follow the same luminosity correlation has important implications for the structures of Seyfert cores. The typical resolution-limit of our imaging corresponds to ~70 pc at a median z=0.01, and we use the tightness of the correlation to place constraints on the dominance of any residual emission sources within these physical scales. An upper-limit for any contaminating star formation of ~40% of the unresolved flux is inferred, on average. We suggest that uncontaminated mid-IR continuum imaging of AGN is an accurate proxy for their intrinsic power. Key words: galaxies: active, infrared: galaxies, X-rays: galaxies, galaxies: Seyfert, accretion, accretion disks
Retrieve 42 NED objects in this reference.
Please click here for ADS abstract

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