NuSTAR Discovery of a Compton-thick, Dust-obscured Galaxy: WISE J0825+3002

We report the discovery of a Compton-thick (CT), dust-obscured galaxy at z = 0.89, WISE J082501.48+300257.2 (WISE 0825+3002), observed by the Nuclear Spectroscopic Telescope Array. X-ray analysis with the XCLUMPY model revealed that hard X-ray luminosity in the rest-frame 2–10 keV band of WISE 0825+3002 is L _X (2–10 keV) = ${4.2}_{-1.6}^{+2.8}\times {10}^{44}$ erg s⁻¹ while its hydrogen column density is N _H = ${1.0}_{-0.4}^{+0.8}\times {10}^{24}$ cm⁻², indicating that WISE 0825+3002 is a mildly CT active galactic nucleus (AGN). We performed spectral energy distribution (SED) fitting with CIGALE to derive its stellar mass, star formation rate, and infrared luminosity. The estimated Eddington ratio based on stellar mass and integration of the best-fit SED of the AGN component is λ _Edd = 0.70, which suggests that WISE 0825+3002 harbors an actively growing black hole behind a large amount of gas and dust. We found that the relationship between the luminosity ratio of X-ray and 6 μm, and Eddington ratio, follows an empirical relation for AGNs reported by Toba et al.