X-Ray Bolometric Corrections for Compton-thick Active Galactic Nuclei

Abstract

We present X-ray bolometric correction factors, (≡ / ), for Compton-thick (CT) active galactic nuclei (AGNs) with the aim of testing AGN torus models, probing orientation effects, and estimating the bolometric output of the most obscured AGNs. We adopt bolometric luminosities, , from literature infrared (IR) torus modeling and compile published intrinsic 2–10 keV X-ray luminosities, , from X-ray torus modeling of NuSTAR data. Our sample consists of 10 local CT AGNs, where both of these estimates are available. We test for systematic differences in values produced when using two widely used IR torus models and two widely used X-ray torus models, finding consistency within the uncertainties. We find that the mean of our sample in the range of is log 10  = 1.44 ± 0.12 with an intrinsic scatter of ∼0.2 dex, and that our derived values are consistent with previously established relationships between and and and Eddington ratio ( ). We investigate if is dependent on by comparing our results on CT AGNs to published results on less-obscured AGNs, finding no significant dependence. Since many of our sample are megamaser AGNs, known to be viewed edge-on, and furthermore under the assumptions of AGN unification whereby unobscured AGNs are viewed face-on, our result implies that the X-ray emitting corona is not strongly anisotropic. Finally, we present values for CT AGNs identified in X-ray surveys as a function of their observed , where an estimate of their intrinsic is not available, and redshift, useful for estimating the bolometric output of the most obscured AGNs across cosmic time.