Ansh, ShreyChen, Chien-Ting J.Brandt, W. N.Hood, Carol E.Kammoun, E. S.Lansbury, G.Paltani, StéphaneReines, Amy E.Ricci, C.Swartz, Douglas A.Trump, Jonathan R.Vito, F.Hickox, Ryan C.2023-03-242023-03-242023-01Ansh, Shrey, Chien-Ting J. Chen, W. N. Brandt, Carol E. Hood, E. S. Kammoun, G. Lansbury, Stéphane Paltani et al. "NuSTAR Observations of a Heavily X-Ray-obscured AGN in the Dwarf Galaxy J144013+ 024744." The Astrophysical Journal 942, no. 2 (2023): 82.0004-637Xhttps://scholarworks.montana.edu/handle/1/17774We present a multiwavelength analysis of the dwarf Seyfert 2 galaxy J144013+024744, a candidate obscured active galactic nucleus (AGN) thought to be powered by an intermediate-mass black hole (IMBH, M • ≈ 104−106 M ⊙) of mass M • ∼ 105.2 M ⊙. To study its X-ray properties, we targeted J144013+024744 with NuSTAR for ≈100 ks. The X-ray spectrum was fitted with an absorbed power law, Pexmon, and a physical model (RXTorus). A Bayesian X-ray analysis was performed to estimate the posteriors. The phenomenological and the physical models suggest the AGN to be heavily obscured by a column density of N H = (3.4–7.0) × 1023 cm−2. In particular, the RXTorus model with a subsolar metallicity suggests the obscuring column to be almost Compton-thick. We compared the 2–10 keV intrinsic X-ray luminosity with the inferred X-ray luminosities based on empirical scaling relations for unobscured AGNs using L [Oiv] 25.89 μm, L [Oiii] λ5007, and L 6μm and found that the high-excitation [Oiv] line provides a better estimate of the intrinsic 2–10 keV X-ray luminosity ( L 2 – 10 int ∼ 10 41.41 erg s−1). Our results suggest that J144013+024744 is the first type 2 dwarf galaxy that shows X-ray spectroscopic evidence for obscuration. The column density that we estimated is among the highest measured to date for IMBH-powered AGNs, implying that a typical AGN torus geometry might extend to the low-mass end. This work has implications for constraining the BH occupation fraction in dwarf galaxies using X-ray observations.en-UScc-byhttps://creativecommons.org/licenses/by/4.0/NuSTARNuSTAR ObservationsX-RayDwarf GalaxyArticle