Unveiling the mass assembly history of the Milky Way via its stellar halo
Danny Horta (The University of Queensland (Australia))
Tuesday 21/06/2022 @ 14:00, Sala IV piano Battiferro
The advent of large-scale stellar surveys in the last few decades have revolutionised the way we can study and analyse the Milky Way Galaxy. Of particular importance has been the discovery of substructures in the stellar halo, conjectured to be the debris from disrupted satellite galaxies accreted via the hierarchical mass assembly formation of galaxies. In this talk, I will first provide evidence for the discovery of a halo substructure buried in the heart of the Milky Way postulated to be debris from a massive and early-accreted disrupted satellite galaxy (dubbed Heracles). Following, I will take a step back and present new results focused on assessing the reality and nature of all substructure identified so far in the stellar halo, based on a chemical composition analysis utilising the latest APOGEE and Gaia data. The findings presented in this talk help elucidate the nature of stellar halo populations, and in turn place constraints on the mass assembly history of the Galaxy.