Presentation #106A.01 in the session Active Galactic Nuclei I.
Observations of high-redshift quasars demonstrate that many supermassive black holes (BHs) reached large masses within one billion years after the Big Bang. However, the origin of the first BHs is still a mystery and poses one of the most fascinating unsolved problems in modern astrophysics. The most promising way to answer this question is to explore the properties of high redshift accreting BHs at z ≥ 6. Typical BHs remain hidden from X-ray surveys due to their relatively faint nature and the limited sensitivity of X-ray telescopes. Gravitational lensing, however, provides a powerful method to study this unique population as it magnifies the faint light from these high redshift sources. In this work, we discuss how gravitational lensing can be used to probe the earliest BHs using two approaches. First, we probe the X-ray emission originating from 155 gravitationally-lensed z ≈ 6 galaxies that were detected in the RELICS survey. Second, we present a unique synergy between Chandra and JWST: we utilize ultra-deep Chandra observations to study the X-ray emission from growing BHs in high-redshift JWST-identified galaxies by harnessing the power of lensing magnification from the galaxy cluster, Abell 2744. We discuss the powerful constraints that can be placed on the origin and early growth of BHs.