Abstract: Dynamical modeling serves as a tool for both archaeology and detection for galaxies. On one hand, stellar motions define galaxy morphology, and their orbits act as fossils of formation history. Combined with stellar populations, stellar orbits can fully uncover a galaxy’s evolutionary history. Using high-quality IFU data within the framework of population–orbit superposition models, for the first time, we have quantified the masses and time of ancient mergers in two nearby galaxies. On the other hand, stellar motions enable the reconstruction of a galaxy’s gravitational potential, making dynamical modeling a key tool to map the dark matter mass distribution. By combining IFU and HI data, we have precisely measured the dark matter distributions of a large sample of nearby galaxies, showing that nearby galaxy centers generally have lower central dark matter densities than predicted by numerical simulations. Furthermore, by developing a data-driven empirical orbit–superposition model and combining LAMOST and Gaia data, we have constrained the 3D shape of the Milky Way’s dark matter halo, providing critical clues to the puzzle of perpendicular alignment of the satellite plane.
Bio: My name is Ling Zhu. I have been leading a research group on galactic dynamics at the Shanghai Astronomical Observatory, Chinese Academy of Sciences since 2018. Before that, I was a postdoctoral researcher at the Max Planck Institute for Astronomy in Heidelberg, Germany from 2013 to 2018. I received my Ph.D. from the Center for Astrophysics, Tsinghua University in 2013, and obtained my Bachelor's degree from the Department of Physics, Tsinghua University, Beijing in 2008.