Abstract: Cosmic dawn, loosely defined here to be the first billion years of cosmic time, is an intriguing era that witnessed the formation of the first generations of galaxies. Towards the end of it there was the last major phase transition of our Universe, the epoch of reionization (EoR), which is believed to be driven by the hydrogen-ionizing radiation background emerged from the early galaxies formed. In this talk, I will explain how cosmic dawn becomes a real exciting epoch for unveiling the physics of galaxy formation thanks to the James Webb Space Telescope (JWST), as well as several forthcoming facilities such as SPHEREx, Roman Space Telescope, and Square Kilometer Array, that will probe the large-scale effects of early galaxy formation. I will discuss the theoretical landscape of galaxy formation at cosmic dawn informed by new JWST observations, with a particular focus on the phenomenon of bursty star formation. I will introduce methods and ideas to shed light on different aspects of early galaxy formation, including the star formation history, stellar feedback, outflows, and the ionizing output, using both individual galaxies and their effects on the large-scale structure as probes. With a few case studies, I will demonstrate how to harness the power of the aforementioned facilities (and their synergies) for unveiling the physical nature of galaxies at cosmic dawn.
Unveiling the Physics of Galaxy Formation and Its Large-scale Effects at Cosmic Dawn
Guochao Sun (Northwestern/CIERA) // November 18, 2024
Abstract: Cosmic dawn, loosely defined here to be the first billion years of cosmic time, is an intriguing era that witnessed the formation of the first generations of galaxies. Towards the end of it there was the last major phase transition of our Universe, the epoch of reionization (EoR), which is believed to be driven by the hydrogen-ionizing radiation background emerged from the early galaxies formed. In this talk, I will explain how cosmic dawn becomes a real exciting epoch for unveiling the physics of galaxy formation thanks to the James Webb Space Telescope (JWST), as well as several forthcoming facilities such as SPHEREx, Roman Space Telescope, and Square Kilometer Array, that will probe the large-scale effects of early galaxy formation. I will discuss the theoretical landscape of galaxy formation at cosmic dawn informed by new JWST observations, with a particular focus on the phenomenon of bursty star formation. I will introduce methods and ideas to shed light on different aspects of early galaxy formation, including the star formation history, stellar feedback, outflows, and the ionizing output, using both individual galaxies and their effects on the large-scale structure as probes. With a few case studies, I will demonstrate how to harness the power of the aforementioned facilities (and their synergies) for unveiling the physical nature of galaxies at cosmic dawn.