The metal-poor thin disc of the Milky Way with Galah and Gaia DR3

In this poster I present the finding of very metal-poor thin-disc-like stars within the Galah survey, confirming a previous discovery using the Pristine photometric database. In line with recent observational studies of Milky-Way metal-poor stars, these results open new questions and add valuable constraints to the research of how the thin disc of the Milk-Way formed. These studies reveal the existence of both kinematical disc-like and halo-like stars along the whole metallicity range down to extremely low metallicities. However, our analysis reveals that the chemo-dynamical properties of the halo and disc populations vary depending on the metallicity regime considered. This characterisation reflects key moments of the Milky-Way history, in particular of the formation of the disc and its settlement in a thin configuration