PACHA: Probing AGN Coronae with High-redshift AGN
Researchers studied 13 high-redshift, radio-quiet quasars to constrain AGN coronal properties using X-ray data from NuSTAR and XMM-Newton. They found mean cutoff energies and temperatures significantly lower than local AGN, suggesting a hybrid corona where non-thermal electrons cool the thermal population. This implies different physical conditions in luminous, high-redshift black hole systems.