093083

The X-ray emission from AGN is believed to be generated from the tiny regionsurrounding the SMBH namely the corona. The cutoff energy in the AGN X-rayspectrum (at a few hundred keV) can be used to probe the coronal properties.However only lower limits to the cutoff energy of low-redshift AGN weremeasured due to the limited bandpass (up to 80 keV). High-z quasarsinstead are the best targets to constrain the cutoff energy thanks tothe cosmological redshifting. So far only four z and amp gt 1 quasars have theircutoff energy constrained. Here we propose other four z and amp gt 1 quasars toincrease the current sample size to statistically constrain the AGN coronalproperties and thus better understand the physics of coronal Comptonization. [truncated! Please see actual data for full text]