Description
With the goal of investigating the role of the Galaxy’s large-scale dynamics on star formation, we use the hydrodynamical AREPO moving-mesh code to perform simulations of the Milky Way. Our models include a live stellar disc and bulge, a live dark matter halo, and a gaseous disc—evolved self-consistently with no fixed potentials and under isothermal equations of state.
We compare our results with 12CO and HI observations of the Milky Way by generating longitude-velocity diagrams of the projected gas surface densities. From these, we extract the skeletons of key features (spiral arms, bar) and terminal velocity contours, which we compare to observations via several diagnostic tools. Combining these, we identify a model that best reproduces the Milky Way’s main features. This model shows multiple transient spiral arms and an inner bar. The gas dynamics reveal a central “butterfly” pattern in radial velocity, characteristic of spiral galaxies, as well as clear streaming motions around spiral arms.
This best-fit model will serve as the base for future simulations including more detailed ISM physics (e.g. chemistry, star formation, feedback) to study how star formation is regulated in the Milky Way. In this talk, I will highlight the need for tailored dynamical models like this for interpreting Galactic-scale star formation. I will present results on the kinematics of gas and stars, and compare them to the latest Gaia DR3 findings—demonstrating the synergy between cutting-edge simulations and observational data in the Gaia era.
