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Detection of type-2 quasars in the radio galaxies B3 0731+438 and 3C 257

P. M. Derry·P. T. O'Brien·J. N. Reeves·M. J. Ward·M. Imanishi·S. Ueno
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Abstract

We present XMM-Newton observations and spectral fitting of two highly 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 powerlaw components. The spectral models indicate that both objects harbour highly obscured nuclei, with N_H ~ 0.5 - 2 x 10^23 cm^-2. Correcting for this absorption we find large intrinsic luminosities in the range L_X ~ 0.2 - 1 x 10^45 erg/s. Thus, both sources are type-2 quasars.

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P. M. Derry, P. T. O'Brien, J. N. Reeves, M. J. Ward, M. Imanishi, S. Ueno. 2003-04-30. Detection of type-2 quasars in the radio galaxies B3 0731+438 and 3C 257. https://doi.org/10.1046/j.1365-8711.2003.06736.x

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