The Ages and Masses of a Million Galactic-Disk Main-Sequence Turnoff and Subgiant Stars from the LAMOST Galactic Spectroscopic Surveys
Maosheng Xiang et al 2017 ApJS 232 2
The large data set of galactic-disk stellar ages and masses from LAMOST suggest that the Milky Way’s thin disk became prominent 8–10 Gyr ago, while the thick disk formed earlier and was almost quenched 8 Gyr ago.