Dept Colloquium: Erini Lambrides, NASA GSFC

Missing the Forest for the Seeds: Uncovering Representative Black Hole Growth at Early Times

Speaker: Erini Lambrides, NASA GSFC

Abstract: With the launch of JWST, we are uncovering a supposed extreme over-abundance and over-massiveness of z>4 supermassive black holes. From X-ray to Radio, expectations built off of pre-JWST predictions fail to reproduce the observed accreting black hole signatures (or lack thereof) of these newly discovered sources. We are potentially on the brink of a paradigm shift in early BH evolution -- but to robustly test and potentially break accepted paradigms, we need deeper observations, with greater resolution, and to move beyond single wavelength regime approaches. In this talk I will highlight our recent works that are centered on detailing the physical nature of the early accreting massive black hole candidates discovered with JWST. Furthermore, while these new sources are exciting, they may only represent the tip of the iceberg of the total massive black hole demography at early times. Heavily obscured AGN, whose accretion signatures are so attenuated they are absent in the very wavelengths JWST probes at early times, are predicted to dominate z>4 BH populations. I will discuss our novel selection algorithm in uncovering multi-band radio coverage. We find these sources live amongst the most massive, star-forming galaxies of their epoch, and I will discuss the implications these results have in the context of feedback and the high-z AGN candidates solely identified with JWST.

Host: Dr. Suvi Gezari