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arXiv · 2208.01627

XMM-Newton and NuSTAR Observations of an Optically Quiescent Quasar

Claire Greenwell·Poshak Gandhi·George Lansbury·Peter Boorman·Vincenzo Mainieri·Daniel Stern
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Abstract

Optically quiescent quasars (OQQs) represent a recently systematised class of infrared-luminous active galactic nuclei (AGN) which have galaxy-like optical continua. They may represent an interesting, brief phase in the AGN life cycle, e.g. either cocooned within high-covering-factor media or indicative of recent triggering, though their nature remains unclear. Here, we present the first targeted simultaneous X-ray observations of an OQQ, our previously identified prototype, SDSS J075139.06+402811.2 at $z$=0.587. The source is significantly detected over 0.5-16 keV with XMM-Newton and NuSTAR, unambiguously confirming the presence of current accretion activity. Spectral modelling yields an intrinsic luminosity $L_{\rm 2-10 keV}$ $\approx$4.4$ \times$10$^{43}$ erg s$^{-1}$, well within the AGN regime, but underluminous relative to its infrared power. It is lightly obscured, with log $N_{\rm H}$ [cm$^{-2}$] $\approx$22.

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Claire Greenwell, Poshak Gandhi, George Lansbury, Peter Boorman, Vincenzo Mainieri, Daniel Stern. 2022-08-02. XMM-Newton and NuSTAR Observations of an Optically Quiescent Quasar. https://doi.org/10.3847/2041-8213%2Fac83a0

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