@article{2b8cee702934499b8aa9b972d9d9cf6f,
title = "Exploratory Chandra observations of the three highest redshift quasars known",
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.",
keywords = "Galaxies: active, Galaxies: nuclei, Quasars: general, X-rays: galaxies",
author = "Brandt, {William N.} and Schneider, {Donald P.} and Xiaohui Fan and Strauss, {Michael A.} and Gunn, {James E.} and Richards, {Gordon T.} and Anderson, {Scott F.} and {Vanden Berk}, {Daniel E.} and Bahcall, {Neta A.} and J. Brinkmann and Robert Brunner and Bing Chen and Hennessy, {G. S.} and Lamb, {Donald Q.} and Wolfgang Voges and York, {Donald G.}",
note = "Funding Information: This work would not have been possible without the enormous efforts of the entire Chandra team. We thank H. D. Tananbaum for kindly allocating the time for these observations and S. N. Virani for help with observation planning. We thank S. C. Gallagher, S. Kaspi, C. Vignali, and an anonymous referee for helpful discussions. We gratefully acknowledge the financial support of NASA LTSA grant NAG 5-8107 (W. N. B.), NSF grant AST 99-00703 (D. P. S., G. T. R.), and NSF grant AST 00-71091 (M. A. S.). The Sloan Digital Sky Survey is a joint project of the University of Chicago, Fermilab, the Institute for Advanced Study, the Japan Participation Group, Johns Hopkins University, the Max-Planck-Institute for Astronomy, the Max-Planck-Institute for Astrophysics, New Mexico State University, Princeton University, the US Naval Observatory, and the University of Washington. Apache Point Observatory, site of the SDSS telescopes, is operated by the Astrophysical Research Consortium. Funding for the project has been provided by the Alfred P. Sloan Foundation, the SDSS member institutions, the National Aeronautics and Space Administration, the National Science Foundation, the US Department of Energy, the Japanese Monbukagakusho, and the Max Planck Society.",
year = "2002",
month = apr,
day = "10",
doi = "10.1086/340581",
language = "English (US)",
volume = "569",
pages = "L5--L9",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "1 II",
}