2018MNRAS.481.4419B

We present measurements of the coronae of two active galactic nuclei (AGNs) from hard X-ray observations made with NuSTAR: ESO 103-035, a moderately to highly obscured source with significant reflection; and IGR 2124.7+5058, a radio-loud source with a very hard spectrum. Using an exponentially cut-off power-law model for the coronal emission spectrum gives a high-energy cut-off of 100_–30⁺⁹⁰ keV for ESO 103-035 and 80_–9⁺¹¹ keV for IGR 2124.7+5058, within the typical range for AGNs. Fitting with physical Comptonization models shows that these correspond to a temperature of 22_–6⁺¹⁹ and 20_–2⁺³ keV, respectively. These values are consistent with pair production limiting the coronal temperature.