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An XMM-Newton detection of the z=5.80 X-ray weak quasar SDSSp J104433.04-012502.2

W. N. Brandt·M. Guainazzi·S. Kaspi·X. Fan·D. P. Schneider·Michael A. Strauss·J. Clavel·J. E. Gunn
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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 alpha_ox=-1.91 +/- 0.05 and a 3.4-13.6 keV luminosity of about 1.8 x 10^{44} erg/s. The most likely reason for its X-ray weakness is heavy absorption with N_H greater than about 10^{24} 1/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 microns to search for blueshifted C IV absorption may elucidate the origin of the X-ray weakness.

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W. N. Brandt, M. Guainazzi, S. Kaspi, X. Fan, D. P. Schneider, Michael A. Strauss, J. Clavel, J. E. Gunn. 2000-10-17. An XMM-Newton detection of the z=5.80 X-ray weak quasar SDSSp J104433.04-012502.2. https://doi.org/10.1086/318760

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