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Due to their heavily obscured central engines, the growth rate of Compton-thick (CT) active galactic nuclei (AGN) is difficult to measure. A statistically significant correlation between the Eddington ratio, {lambda}$_{Edd}$, and the X-ray power-law index, {Gamma}, observed in unobscured AGN offers an estimate of their growth rate from X-ray spectroscopy (albeit with large scatter). However, since X-rays undergo reprocessing by Compton scattering and photoelectric absorption when the line-of-sight to the central engine is heavily obscured, the recovery of the intrinsic {Gamma} is challenging. Here we study a sample of local, predominantly Compton-thick megamaser AGN, where the black hole mass, and thus Eddington luminosity, are well known. We compile results on X-ray spectral fitting of these sources with sensitive high-energy (E> 10 keV) NuSTAR data, where X-ray torus models which take into account the reprocessing effects have been used to recover the intrinsic {Gamma} values and X-ray luminosities, L$_X$. With a simple bolometric correction to L$_X$ to calculate {lambda}$_{Edd}$, we find a statistically significant correlation between {Gamma} and {lambda}$_{Edd}$ (p = 0.007). A linear fit to the data yields {Gamma} = (0.41$pm$0.18)log$_{10}${lambda}$_{Edd}$+(2.38$pm$ 0.20), which is statistically consistent with results for unobscured AGN. This result implies that torus modeling successfully recovers the intrinsic AGN parameters. Since the megamasers have low-mass black holes (M$_{BH}approx10^6-10^7$ M$_{sol}$) and are highly inclined, our results extend the {Gamma}-{lambda}$_{Edd}$ relationship to lower masses and argue against strong orientation effects in the corona, in support of AGN unification. Finally this result supports the use of {Gamma} as a growth-rate indicator for accreting black holes, even for Compton-thick AGN.
We present X-ray bolometric correction factors, $kappa_{Bol}$ ($equiv L_{Bol}/L_X$), for Compton-thick (CT) active galactic nuclei (AGN) with the aim of testing AGN torus models, probing orientation effects, and estimating the bolometric output of th
We present the first study of an Iwasawa-Taniguchi/X-ray Baldwin effect for Compton-thick active galactic nuclei (AGN). We report a statistically significant anti-correlation between the rest-frame equivalent width (EW) of the narrow core of the neut
We analyzed the spectral shape of the Compton shoulder around the neutral Fe-K$_alpha$ line of the Compton-thick type II Seyfert nucleus of the Circinus galaxy. The characteristics of this Compton shoulder with respect to the reflected continuum and
We analyze observations obtained with the Chandra X-ray Observatory of bright Compton thick active galactic nuclei (AGNs), those with column densities in excess of 1.5 x 10^{24} cm^{-2} along the lines of sight. We therefore view the powerful central
We have analyzed the broadband X-ray spectra of active galactic nuclei (AGNs) in two non-merging luminous infrared galaxies (LIRGs) UGC 2608 and NGC 5135, utilizing the data of NuSTAR, Suzaku, XMM-Newton, and Chandra. Applying the X-ray clumpy-torus