Contributed Talk - Splinter Computation

Thursday, 24 September 2020, 09:54   (virtual room B)

The diverse evolutionary pathways of Milky Way-like galaxies with TNG50

Diego Sotillo Ramos, Annalisa Pillepich
Max-Planck-Institut für Astronomie

The formation and evolution of the Milky Way and analog disc galaxies is a complex process whose detailed description and comprehension is still incomplete despite the countless observations and simulations carried out in recent years to shed light on the various factors that may play a role shaping this type of galaxies: mergers and accretion events, stellar migration, etc. Making use of the high-resolution cosmological simulation IllustrisTNG50 we identify the best MW-like analogs (selected by either halo or stellar mass and stellar shape) to answer the question of how many pathways can lead to the formation of a MW-like galaxy at z=0. Being able to track the evolution of their structural properties with time we discover that a large diversity of histories unveils when exploring in detail the mass, size, shape, structure and assembly history of these galaxies, although some common trends can also be recognized: the total stellar content remains almost stable since redshift=1 or the stellar half mass radius tends to grow linearly with time. We are also able to compare this set of galaxies with other galaxies present in the simulated volume that share only some of the MW-like properties (e.g. mass range but not shape) to study the most important differences: we will reveal a quite significant divergence in the gas fraction for each of both samples or in the supermassive black hole growth.