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Exploratory Chandra Observations of the Three Highest Redshift Quasars Known

W. N. Brandt·D. P. Schneider·X. Fan·M. A. Strauss·J. E. Gunn·G. T. Richards·S. F. Anderson·D. E. Vanden Berk·N. A. Bahcall·J. Brinkmann·R. Brunner·B. Chen·G. S. Hennessy·D. Q. Lamb·W. Voges·D. G. York
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Abstract

We report on exploratory Chandra observations of the three highest redshift quasars known (z = 5.82, 5.99, and 6.28), all found in the Sloan Digital Sky Survey. These data, combined with a previous XMM-Newton observation of a z = 5.74 quasar, form a complete set of color-selected, z > 5.7 quasars. X-ray emission is detected from all of the quasars at levels that indicate that the X-ray to optical flux ratios of z ~ 6 optically selected quasars are similar to those of lower redshift quasars. The observations demonstrate that it will be feasible to obtain quality X-ray spectra of z ~ 6 quasars with current and future X-ray missions.

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W. N. Brandt, D. P. Schneider, X. Fan, M. A. Strauss, J. E. Gunn, G. T. Richards, S. F. Anderson, D. E. Vanden Berk, N. A. Bahcall, J. Brinkmann, R. Brunner, B. Chen, G. S. Hennessy, D. Q. Lamb, W. Voges, D. G. York. 2002-03-08. Exploratory Chandra Observations of the Three Highest Redshift Quasars Known. https://doi.org/10.1086/340581

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