Galactic Archaeology with RAVE: Clues to the Formation of the Thick Disk

Understand

I present an analysis of ~13000 stars from RAVE Data Release 4 (DR4) to better understand the formation of the thick disk.

• The stars I consider are mostly within 1 kpc of the Sun.
• Based on a Monte-Carlo analysis of the data and comparison with a toy model, I suggest the thick disk formed fairly rapidly when [Mg/Fe] ${\approx}$0.2-0.3.
• We consider an origin via direct accretion unlikely as the thick disk is fast-rotating and fairly metal-rich for its age.