Broad-band X-ray spectrum of the newly discovered broad-line radio galaxy IGR J21247+5058

Abstract

In this paper, we present radio and high-energy observations of the INTEGRAL source IGR J21247+5058, a broad line emitting galaxy obscured by the Galactic plane. Archival Very Large Array radio data indicate that IGR J21247+5058 can be classified as an Faranoff–Riley type II Broad-Line Radio Galaxy. The spectrum between 610 MHz and 15 GHz is typical of synchrotron self-absorbed radiation with a peak at 8 GHz and a low-energy turnover; the core fraction is 0.1 suggestive of a moderate Doppler boosting of the base of the jet. The high-energy broad-band spectrum was obtained by combining XMM–Newton and Swift/X-Ray Telescope (XRT) observation with INTEGRAL/Image on Board Integral Satellite (IBIS) data. The 0.4–100-keV spectrum is well described by a power law, with slope Γ= 1.5, characterized by complex absorption due to two layers of material partially covering the source and a high-energy cut-off around 70–80 keV. Features such as a narrow iron line and a Compton reflection component, if present, are weak, suggesting that reprocessing of the power-law photons in the accretion disc plays a negligible role in the source.