Journal Club


"Discovery of 21 New Changing-Look AGNs"

Swayamtrupta Panda (NCAC, Warsaw)

The talk is based on


"AGN and Relativistic Corrections of Cutoff Energy "

Lydia Stofanova (Czeska Akademia Nauk)

Hard X-ray spectra of accreting black holes in active galactic nuclei are characterized by a power-law shape with an exponential cut-off energy at several tens up to a few hundred of keV. The value of the cut-off energy is related with the temperature of a hot corona that reprocesses and inversely Comptonise thermal emission from the accretion disc. The exact geometry of the corona is, however, unknown. Several observations suggest it to be very compact and in a close proximity to the compact black hole. Such location implies strong relativistic effects on the resulting spectra.