K. Koyama, H. Awaki, K. Iwasawa, M.J. Ward

Abstract

We report the first detection of hard X-rays (above 2 keV), from the narrow-line radio galaxy (NLRG) IC 5063. The hard X-ray spectrum is described by a power-law photon index of 1.5 with a large absorption corresponding to the N(H) value of 2 x 10 exp 23 H/sq cm. The X-ray luminosity (2-20 keV band) after the correction of the absorption is 2.5 x 10 exp 43 ergs/s. Since the X-ray luminosity and spectral index are in the range found for Seyfert 1's and broad-line radio galaxies (BLRG), we conclude that IC 5063 has an intrinsic BLRG type nucleus hidden behind a high gas column. There is a hint of X-ray flux variations with time scales between 1000 s and 10 hr which, if confirmed, would further support that the hard X-rays are the direct beam from a compact nucleus penetrating the high gas column.