Chemo-dynamical Simulations and Galactic Archaeology

Abstract

We predict the frequency distribution of elemental abundance ratios from Carbon to Zinc as a functions of time and location, which can be directly compared with the next generation of the galactic archeology project such as the HERMES. We perform the chemodynamical simulations of a Milky Way-type galaxy from a CDM initial condition, using a self-consistent hydrodynamical code with supernova feedback and chemical enrichment. In the simulated galaxy, the kinematical and chemical properties of the bulge, disk, and halo are consistent with the observations. The bulge have formed from the assembly of subgalaxies at z greater than or similar to 2, and have higher [alpha/Fe] ratios because of the lack of contribution of Type Ia Supernovae. The disk have formed with a constant star formation over 13 Gyr, and shows a decreasing trend of [alpha/Fe] and increasing trends of [(Na,Al,Cu,Mn)/Fe]. However, the thick disk stars tend to have higher [alpha/Fe] and lower [Mn/Fe] than thin disk stars. 60% of the thick disk stars have formed in the satellite galaxies before they accrete on the disk in this CDM-based simulation.