Affiliation: University of Geneva

Contribution: Oral

Title: Studying extremely dust-obscured massive galaxies in the early Universe with JWST and ALMA

Abstract: Recent studies have unveiled the existence of extremely dust-obscured massive galaxies at z>3 and into the reionization epoch. This has significant implications for our understanding of early galaxy build-up and the cosmic star formation history. In this talk, I will first present our recent findings on these galaxies with JWST FRESCO survey and GOODS-ALMA survey. Based on the unprecedented imaging and spectroscopic data from the JWST FRESCO survey, we can systematically determine their spectroscopic redshifts, thus vastly improving constraints on their physical properties. In addition, I will show several extremely massive dusty galaxies at zspec > 5, that may challenge the current galaxy assembly models. I will discuss their ultra-massive properties, dust-obscured star formation rates, and the possibility of the existence of AGN. Some of these ultra-massive galaxies have been confirmed to be located in a dense environment. Second, I will discuss our recent morphological and cluster analysis studies of these extremely dust-obscured massive galaxies, based on multiple JWST surveys (CEERS, FRESCO, PRIMER, etc.). Through morphological and clustering studies, we investigate the evolution of these massive and dusty star-forming galaxies and their connection to low-redshift massive passive galaxies, and also link the formation of these galaxies to the UV-luminous galaxies at earlier redshift. Finally, I will discuss our future plans, including the recently approved JWST project.

This contribution can be found here (pdf).