A Deep Analysis of Nearby Heavily Obscured AGN with XMM-Newton and NuSTAR

The cosmic X-ray background (CXB) is thought to be mainly produced by obscured and unobscured active galactic nuclei (AGN). Compton-thick (CT-) AGNs (with absorbing column density NH > 10²⁴ cm^-2) are responsible for ~30% of the CXB at its peak and are expected to be numerous in population (30-50% as predicted by population synthesis models). However, as of today, CT-AGNs have never been detected in large numbers, with their observed fraction in the local universe being only ~5-10%. I present the results of a deep look at our sample of nearby heavily obscured AGN with XMM-Newton and NuSTAR. These AGN have been selected using criteria previously proven to discover CT-AGN, giving us a better understanding of the physics of the AGN obscuration process.