Detection of type - 2 quasars in the radio galaxies B 3 0731 + 438 and 3 C 257
نویسنده
چکیده
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 NH ≈ 0.5 − 2 × 10 23 cm. Correcting for this absorption we find large intrinsic luminosities in the range LX ≈ 0.2 − 1 × 10 45 erg s. Thus, both sources are type-2 quasars.
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