Using N-body simulations to understand the chemo-dynamical evolution of the inner Milky Way

TL;DR

This paper demonstrates how chemo-dynamical N-body simulations can elucidate the structure, formation, and evolution of the inner Milky Way, revealing the relationships between kinematics, morphology, and chemistry.

Contribution

It introduces the use of chemo-dynamical N-body simulations to interpret the complex structure and formation history of the inner Galaxy.

Findings

Thick disc stars formed earlier than thin disc stars.

The thick disc's bar is thicker and has a different vertical morphology.

The inner disc scalelength is smaller than in similar nearby galaxies.

Abstract

I present examples of how chemo-dynamical N-body simulations can help understanding the structure and evolution of the inner Galaxy. Such simulations reproduce the observed links between kinematics, morphology and chemistry in the bar/bulge region and explain them by the self-consistent cohabitation of a number of components. Galactic archaeology, applied to simulation snapshots, explains the sequence in which the stars of the various components were formed. The thick disc stars form earlier than those of the thin disc and in a much shorter time scale. The bar in the thick disc is horizontally thicker than that of the thin disc and has a different vertical morphology. The Galaxy's inner disc scalelength is much smaller than what is expected from nearby galaxies of similar stellar mass.