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 L2−10keV≈4.4×1043 erg s−1, well within the AGN regime, but underluminous relative to its infrared power. It is lightly obscured, with log NH [cm−2] ≈22.
@article{arxiv.2208.01627,
title = {XMM-Newton and NuSTAR Observations of an Optically Quiescent Quasar},
author = {Claire Greenwell and Poshak Gandhi and George Lansbury and Peter Boorman and Vincenzo Mainieri and Daniel Stern},
journal= {arXiv preprint arXiv:2208.01627},
year = {2022}
}
Comments
10 pages, 4 figures, 1 table. Accepted for publication in ApJL