X-ray analysis of SDSS J165202.60+172852.4, an obscured quasar with outflows at peak galaxy formation epoch

Abstract

We report on deep XMM-Newton and NuSTAR observations of the high redshift, z=2.94, extremely red quasar (ERQ), SDSS J165202.60+172852.4, with known galactic ionized outflows detected via spatially-resolved [OIII] emission lines. X-ray observations allow us to directly probe the accretion disk luminosity and the geometry and scale of the circumnuclear obscuration. We fit the spectra from the XMM-Newton/EPIC and NuSTAR detectors with a physically motivated torus model and constrain the source to exhibit a near Compton-thick column density of $N_H=(1.02_{-0.41}^{+0.76})\times 10^{24}{\text{ cm}}^{-2}$, a near edge-on geometry with the line-of-sight inclination angle of $\hat{I}{¸}_i=85^{\circ }$, and a scattering fraction of $f_{sc}\sim 3$ %. The absorption-corrected, intrinsic 2-10 keV X-ray luminosity of $L_{\text{2-10}}=(1.4_{-1}^{+1})\times 10^{45}{\text{ erg s}}^{-1}$ reveals a powerful quasar that is not intrinsically X-ray weak, consistent with observed trends in other ERQs. We also estimate the physical properties of the obscuration, although highly uncertain: the warm ionized scattering density of $n_e\sim 7.5\times (10^2-10^3){\text{ cm}}^{-3}$ and the obscuration mass of $M_{obsc}\sim 1.7\times (10^4-10^6)M_{\odot }$. As previously suggested with shallower X-ray observations, optical and infrared selection of ERQ has proved effective in finding obscured quasars with powerful outflow signatures. Our observations provide an in-depth view into the X-ray properties of ERQs and support the conclusions of severely photon-limited studies of obscured quasar populations at high redshifts.

Accepted for publication in MNRAS. 12 pages, 6 Figures, 4 Tables