The barred inner Milky Way: dynamical models from surveys

TL;DR

This review discusses recent dynamical and chemo-dynamical models of the Milky Way's inner regions, highlighting new insights into its structure, mass distribution, and stellar populations based on survey data.

Contribution

It provides a comprehensive overview of recent models and findings about the Milky Way's inner structure, incorporating new survey data and analysis.

Findings

Determined stellar masses for Galactic components

Identified need for a dark matter core

Revised pattern speed with corotation at ~6 kpc

Abstract

The Milky Way is a barred galaxy whose central bulge has a box/peanut shape and consists of multiple stellar populations with different orbit distributions. This review describes dynamical and chemo-dynamical equilibrium models for the Bulge, Bar, and inner Disk based on recent survey data. Some of the highlighted results include (i) stellar mass determinations for the different Galactic components, (ii) the need for a core in the dark matter distribution, (iii) a revised pattern speed putting corotation at ~6 kpc, (iv) the strongly barred distribution of the metal-rich stars, and (v) the radially varying dynamics of the metal-poor stars which is that of a thick disk-bar outside ~1 kpc, but changes into an inner centrally concentrated component with several possible origins. On-going and future surveys will refine this picture, making the Milky Way a unique case for studying how similar galaxies form and evolve.