Detection of type 2 quasars in the radio galaxies B3 0731+438 and 3C 257
O'Brien, P. T.; Reeves, J. N.; Ward, M. J.; Imanishi, M.; Ueno, S.; Derry, P. M.
United Kingdom, Japan
Abstract
We present XMM-Newton observations and spectral fitting of two high-redshift, [OIII]-luminous, narrow-line radio galaxies, B3 0731+438 and 3C 257. Their X-ray continua are well fitted by a partial covering model with intrinsically unabsorbed and absorbed power-law components. The spectral models indicate that both objects harbour highly obscured nuclei, with NH~ 0.5-2 × 1023 cm-2. Correcting for this absorption we find large intrinsic luminosities in the range LX~ 0.2-1 × 1045 erg s-1. Thus, both sources are type 2 quasars.