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.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science