Ja En つくば宇宙フォーラム
第160回
X-ray AGN in the High Redshift Universe
バーロウホール カサンドラ 氏
筑波大学
要旨
Among the most energetic processes in the Universe, Active Galactic Nuclei (AGN) have been found throughout cosmic history; powered by a central Supermassive Black Hole (SMBH) with those at $z\gtrsim6$ being comparable in mass to SMBHs at $z\sim1$. The formation mechanism of SMBHs remains the subject of much debate, yet AGN are thought to have intrinsic links to the growth of their host galaxies. Understanding the rapid mass growth of SMBHs that must be occurring during this epoch—and crucially their impact on host galaxies—is vital to our understanding of the early Universe. X-rays are often used as a principal tracer of AGN activity, thanks to uncontaminated AGN selection using X-rays and well-defined sensitivity of X-ray surveys. However, with the sensitivity provided by JWST many more AGN have been found within this high-redshift regime than expected from model extrapolations of X-ray measurements below $z\sim6$. In this talk I will summarise the nature of AGN and their role in the early Universe; from the seeding mechanisms of Supermassive Black Holes to the latest results of high-z AGN studies, and present the latest improvements in X-ray constraints on the AGN population.