Oral Presentation

Unveiling the Nature of Dark Galaxies with the IllustrisTNG Simulation

Author(s): Gain Lee, and Ho Seong Hwang

Presenter: Gain Lee (Seoul National University)

Dark galaxies are hypothetical objects believed to be made up almost entirely of dark matter, with little or no stars, making them challenging to detect because of their faintness. There have been several candidates of dark galaxies proposed from observations, but their existence is still under debate and further studies on their nature is necessary to prove or refute them. In this context, we use the IllustrisTNG simulation (TNG50-1) to investigate the properties of dark galaxies and to understand their origin. We identify dark galaxies that have a stellar mass less than 1/10000 of the total mass, and compare their physical properties with those of normal galaxies. Here, we report our findings on (1) the spatial distribution of dark galaxies, (2) their physical properties including size, morphology, and gas temperature, and (3) their evolutionary history, including environments, merger, and SFR history. We also discuss the origin of dark galaxies and provide insights for finding them in the real world.