The Dual Origin of Galactic Stellar Halos
Adi Zolotov (NYU)
Accreted stellar halos are a natural consequence of galaxy formation in a Lambda-CDM Universe, and are widely considered to contain unique fossil records of hierarchical galaxy formation. Observational results, however, have shown that the stellar halo of the Milky
Way was likely assembled through a complex combination of both hierarchical accretions, and in situ star formation. While observational studies of Milky Way halo stars have sought to place constraints on the formation of the Galactic halo, disentangling the relative contributions of such different formation mechanisms has proven to be difficult. In this talk I will describe the stellar halos surrounding Milky Way massed disk galaxies simulated using high resolution cosmological SPH + N-Body simulations. In particular, I will focus on the different physical processes which contribute to the formation of these stellar halos, and how chemical abundances may be used to study and identify the observable imprints of the Milky Way's formation history.