An XMM-Newton detection of the z = 5.80 X-ray-weak quasar SDSSp J104433.04012502.2

W. N. Brandt, M. Guainazzi, S. Kaspi, X. Fan, D. P. Schneider, Michael A. Strauss, J. Clavel, J. E. Gunn

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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.

Original languageEnglish (US)
Pages (from-to)591-597
Number of pages7
JournalAstronomical Journal
Issue number2
StatePublished - Feb 2001

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science


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