An XMM-Newton Detection of the Z=5.80 X-Ray-Weak Quasar SDSSP J104433.04-012502.2
Brandt, W. N.; Clavel, J.; Strauss, Michael A.; Guainazzi, M.; Fan, X.; Schneider, D. P.; Kaspi, S.; Gunn, J. E.
United States, Spain
Abstract
We report on an XMM-Newton observation of the most distant known quasar, SDSSp J104433.04-012502.2, at z=5.80. We have detected this quasar with high significance in the rest-frame 3.4-13.6 keV band, making it the most distant cosmic object detected in X-rays 32+/-9 counts were collected. SDSSp J104433.04-012502.2 is notably X-ray-weak relative to other luminous, optically selected quasars, with αox=-1.91+/-0.05 and a 3.4-13.6 keV luminosity of ~1.8×1044 ergs s-1. The most likely reason for its X-ray weakness is heavy absorption with NH>~1024 cm-2, as is seen in some broad absorption line quasars and related objects; we discuss this and other possibilities. High-quality spectroscopy from 0.95-1.10 μm to search for blueshifted C IV absorption may elucidate the origin of the X-ray weakness.