The thin and thick disks of the galaxy: Differences in evolution

Abstract

The chemical evolution of the Galactic disk was investigated in framework of the opened two-zone model with gas inflow. We suppose that the Galactic disk is divided in two zones — the thin and thick disks, which separate chemically and spatially and have different evolution timescales. The Galactic evolution of magnesium was investigated for the thin and thick disks. The obtained results show that the star formation history of the thin disk is more smooth and quiet than the star formation history of the thick disk of our Galaxy. Gas infall plays an important role in creating relative abundance differences between the thin and thick disk — the inflow rate is more intense for the thick disk.