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

TL;DR

This study presents radio and X-ray observations of the newly identified broad line radio galaxy IGR J21247+5058, revealing its synchrotron spectrum, moderate jet Doppler boosting, and a broad-band X-ray spectrum with complex absorption and weak reprocessing features.

Contribution

It provides the first detailed broadband X-ray spectrum and radio characterization of IGR J21247+5058, classifying it as an FRII broad line radio galaxy with specific spectral features.

Findings

Radio spectrum peaks at 8 GHz with synchrotron self-absorption

X-ray spectrum shows a power law with photon index 1.5 and high energy cutoff around 70-80 keV

Weak reprocessing features suggest minimal disk reflection

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 VLA radio data indicate that IGR J21247+5058 can be classified as an FRII 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/XRT observation with INTEGRAL/IBIS data. The 0.4-100 keV spectrum is well described by a power law, with slope $\Gamma$=1.5, characterised 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 disk plays a negligible role in the source.