Compton-Thick AGN in the NuSTAR ERA VII. A joint NuSTAR, Chandra, and XMM-Newton Analysis of Two Nearby, Heavily Obscured Sources

We present the joint Chandra, XMM-Newton, and NuSTAR analysis of two nearby Seyfert galaxies, NGC 3081 and ESO 565-G019. These are the only two having Chandra data in a larger sample of 10 low-redshift (z ≤ 0.05), candidates Compton-thick (CT) Active Galactic Nuclei selected in the 15-150 keV band with Swift-BAT that were still lacking NuSTAR data. Our spectral analysis, performed using physically motivated models, provides an estimate of both the line-of-sight (l.o.s.) and average (NH,S) column densities of the two torii. NGC 3081 has a Compton-thin l.o.s. column density NH,z = [0.58-0.62] × 1024 cm-2, but the NH,S, beyond the CT threshold (NH,S = [1.41-1.78] × 1024 cm-2), suggests a "patchy"scenario for the distribution of the circumnuclear matter. ESO 565-G019 has both CT l.o.s. and NH,S column densities (NH,z > 2.31 × 1024 cm-2 and NH,S > 2.57 × 1024 cm-2, respectively). The use of physically motivated models, coupled with the broad energy range covered by the data (0.6-70 keV and 0.6-40 keV, for NGC 3081 and ESO 565-G019, respectively) allows us to constrain the covering factor of the obscuring material, which is CTOR = [0.63-0.82] for NGC 3081, and CTOR = [0.39-0.65] for ESO 565-G019.