This Wednesday Mac McMullan, Durham University, will join us to speak on Dwarf Galaxy Growth: A Large Volume, High Resolution Exploration in GALFORM
Due to the small size and relatively ancient nature of their stars, dwarf galaxies are excellent probes of early galaxy formation, and feedback effects from star formation. We have used the high-resolution DM-only simulation COCO combined with the GALFORM semi-analytic model to explore the dependance of stellar mass assemblies of dwarf galaxies (from 10^3 - 10^9) on their environments. We explore different definitions of environment: morphological classifications of voids and nodes of the cosmic web, as well as a definition of environment based on local mass density. Our results show that galaxies in the densest environments assemble their mass first, and galaxies in the least dense environments have delayed assembly, and these trends are much stronger in satellite galaxies than in centrals. This is due to the significant difference in infall times of satellites between different areas of the cosmic web.Additionally, the smallest galaxies have their mass assembly halted early due to reionisation across all environments.
Our research demonstrates the importance of galaxy environment in the assembly of stellar mass, while also situating it in the context of the more important factors: final day mass and the type of galaxy (satellite or central). This is the first exploration of this question extended to the ultra faint regime of dwarf galaxies.