The Galaxy and its stellar halo: insights on their formation from a hybrid cosmological approach

Understand

We use a series of high-resolution simulations of a `Milky-Way' halo coupled to semi-analytic methods to study the formation of our own Galaxy and of its stellar halo.

• The physical properties of our model Milky Way, as well as the age and metallicity distribution of stars in the different components, are in relatively good agreement with observational measurements.
• Assuming that the stellar halo builds up from the cores of the satellite galaxies that merged with the Milky Way over its life-time, we are able to study the physical and structural properties of this component.
• In agreement with previous work, we find that the largest contribution to the stellar halo should come from a few relatively massive (10^8 - 10^10 Msun) satellites, accreted at early times.