Schwarzschild model of Milky Way for Galactic and Extragalactic Archaeology

• Applicant: Sergey Khoperskov, Ph.D.
• Subject Area: Astrophysics and Astronomy
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 565703206

The proposed research aims to deepen our understanding of the Milky Way’s structure, evolution, and its place within the broader context of galaxy formation and dynamics and to unravel the intricate chemo-kinematic properties and 3D mass distribution in our Galaxy.At the heart of the project is the development of a fully self-consistent Schwarzschild orbital superposition framework for resolved stellar populations that not only reconstructs the Milky Way’s stellar distribution function but also simultaneously constrains its baryonic and dark matter mass distributions. This innovative approach will integrate 6D phase-space information of resolved stellar populations from Gaia DR4 and large-scale spectroscopic surveys such as APOGEE, Galah, and the forthcoming SDSS-V and 4MOST. By incorporating stellar age catalogues and empirical birth radii estimations, the project will deliver a spatially resolved star formation history of the Milky Way, providing critical insights into its assembly and chemical enrichment over cosmic time.A key aspect of the research involves exploring the signatures of disequilibrium phenomena within the Milky Way, including the influence of spiral arms, the evolving bar, and interactions with nearby systems such as the Sgr dwarf galaxy and LMC. These investigations will be supported by advanced N-body and hydrodynamical simulations tailored to replicate the Milky Way’s current state and to assess the impact of such interactions on its stellar populations, gas dynamics, and overall morphology. This will allow us to disentangle equilibrium features from disequilibrium effects, shedding light on the complex interplay of internal and external forces shaping the Galaxy.To bridge Galactic and extragalactic studies, the project will generate mock IFU observations of the Milky Way using data derived from the Schwarzschild model and enhanced by non-equilibrium simulations. These mock data cubes will emulate observations from instruments like MUSE and the upcoming BlueMUSE, enabling not just a direct comparison but the exact prediction of how extragalactic Milky Way analogues should appear. By reconstructing age-metallicity distributions and kinematic features, such as the α-element bimodality and age-velocity-metallicity relations, the project will evaluate the Milky Way’s typicality within the broader population of spiral galaxies observed in surveys like MaNGA and GECKOS.

• DFG Programme: Research Grants