The Compton-thick quasar at the heart of the high-redshift giant radio galaxy 6C0905+39

Abstract

Our XMM-Newton spectrum of the giant, high-redshift (z = 1.88) radio galaxy 6C0905+39 shows that it contains one of the most powerful, high redshift, Compton-thick quasars known. Its spectrum is very hard above 2keV. The steep XMM-Newton spectrum below that energy is shown to be due to extended emission from the radio bridge using Chandra data. The nucleus of 6C0905+39 has a column density of 3.5^+1.4_-0.4 × 10²⁴cm^-2 and absorption-corrected X-ray luminosity of 1.7^+0.9_-0.1 × 10⁴⁵ergs^-1 in the 2-10keV band. A lower redshift active galaxy in the same field, SDSS J090808.36+394313.6, may also be Compton thick.