Coronal temperatures of the AGN ESO 103-035 and IGR 2124.7+5058 from NuSTAR observations

TL;DR

This study measures the coronal temperatures of two active galactic nuclei using NuSTAR X-ray observations, revealing values consistent with pair production limits and contributing to understanding AGN coronae.

Contribution

First to analyze the coronal temperatures of ESO 103-035 and IGR 2124.7+5058 using NuSTAR data with physical Comptonisation models.

Findings

Coronal temperatures of 22 keV and 20 keV for the two AGN.

High-energy cut-offs consistent with typical AGN ranges.

Temperatures align with pair production constraints.

Abstract

We present measurements of the coronae of two AGN 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 powerlaw 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 AGN. Fitting with physical Comptonisation 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.