Title: Nailing down the Evolution of the IGM in the Post-Reionization Era Through High-Resolution Simulations

Speaker: Dr. Paulo Montero (Pengcheng Laboratory)

Time: 15:30pm, March 7, 2023

Location: 5-516, PMO Xianlin Campus

Abstract: Cosmic reionization corresponds to the milestone of the Universe where the intergalactic medium transitions from primarily neutral, dark, and cold into mainly ionized, more luminous, and warmer. During this transition, the intergalactic medium is violently heated and ripples from the additional injected energy can be seen millions of years after this milestone. However, estimates of these ripples tend to focus on large scales (a choice that was partially motivated by computational resources). In this talk, I will describe the thermodynamic and hydrodynamic response of the often forgotten intergalactic medium small-scale structure to the reionization process. Furthermore, I will showcase how this response leads to observational “fossils” that can be observed in both current Lyman-alpha forest surveys (e.g. DESI) and nearfuture 21 cm line intensity mapping experiments (e.g. SKA/PUMA). Likewise, I will highlight the physical gains of this effect as a window into the physics that govern cosmic reionization and the Cosmic dawn, and ultimately as a competitive probe of the nature of dark matter.