The Stellar Population of the Thin Disk

TL;DR

This paper reviews recent observations of stars in the Milky Way's thin disk, highlighting complex patterns in their properties and discussing implications for galaxy formation theories.

Contribution

It synthesizes observational data on thin disk stars and discusses the challenges of modeling the Galaxy's formation and evolution.

Findings

Complex kinematic and compositional patterns in thin disk stars

Galactic disk data compatible with hierarchical galaxy formation theories

Need for extensive stellar observations to understand galaxy physics

Abstract

We discuss recent observations of stars located close to the symmetry plane of the Milky Way, and examine them in the context of theories of Galaxy formation and evolution. The kinematics, ages, and compositions of thin disk stars in the solar neighborhood display complex patterns, and interesting correlations. The Galactic disk does not seem to pose any unsurmountable obstacles to hierarchical galaxy formation theories, but a model of the Milky Way able to reproduce the complexity found in the data will likely require a meticulous study of a significant fraction of the stars in the Galaxy. Making such an observational effort seems necessary in order to make a physics laboratory out of our own galaxy, and ultimately ensure that the most relevant processes are properly understood.