I will first review the progress in surveys of the most distant quasars, including the latest record-breaking luminous quasars discovered by Euclid at z>7.5. They are powered by billion solar mass black holes, possible only by a combination of massive early black hole seeds with highly efficient and sustained accretion. I will present the first direct measurements of the central black hole masses, their host galaxies and large scale environment in the earliest quasars using JWST and ALMA. JWST observations have revealed a new population of active galactic nuclei (AGN), the "Little Red Dots" (LRDs), with high abundance and multiwavelength properties different from those of typical AGN and quasars. I will discuss the observations of LRDs and constraints on their physical nature in relation to early black hole growth and focus on the discovery of LRDs in the low-redshift universe. High quality observations of local LRDs, from high resolution spectroscopy, to polarimetry and long-term variability studies, strongly suggest the presence of optically-thick and clumpy gas envelops surrounding the LRD central energy source, consistent with scenarios of super-Eddington accretion, and could be the missing link between black hole seeds and luminous early quasars.
Speaker: Xiaohui Fan, University of Arizona
Host: Allison Strom
CIERA Astrophysics
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