Project 32:
Stellar streams, the remnants of tidally disrupted globular clusters and dwarf galaxies, serve as remarkable tracers for investigating the gravitational potential of the Milky Way (MW) and its dark matter (DM) distribution. These elongated structures are highly sensitive to changes in the underlying potential, and their morphology and kinematics along their orbits can provide crucial insights into the shape and size of the MW’s mass distribution. A key aspect of this project is the identification of stellar streams traversing resonant orbital regions. Through categorization of unique morphological features such as stream gaps or bifurcations, these potentially resonant regions can be identified. By studying streams in resonance, we can obtain a more detailed understanding of the structure of the MW’s potential and its evolution over time. The project will employ observational data from ongoing surveys, such as Gaia, DESI, and LSST, to detect and characterize stellar streams. Advanced numerical simulations from the FIRE-2 collaboration will be used to model the evolution of streams in various gravitational potentials, allowing for a direct comparison with observational data. By iteratively refining the models to match the observed stream properties, we can derive robust constraints on the shape and time evolution of the potential, shedding light on the hierarchical formation of the galaxy.
The student will be the main investigator of writing programs to 1) make use and analyze the modeled data and 2) incorporate and compare with the observational data. The student will discuss with me about the physics involved, the implications of the research goal and findings, and the results from the comparison. Having an extensive experience in coding and utilizing astronomical simulation data and platforms, the student has already begun this work this semester (Spring 2024) and has some very impressive results of plots and animations identifying the resonant regions in the orbital phase. The student also has a very solid physics, math, and astrophysics background and is able to conduct most of this research independently already. Therefore, the modeling and physics aspects of this research project are already very solid, but to complete the analysis, the student will work with me to download observational data and incorporate them into the analysis. I will provide the guidance of data download, interpretation, and discussion of the result. We estimate 20 hours of work/ week for both semesters. (I would like to add that the student has a very high potential, talent, and motivation, in astrophysics, as well as a graduate-student-level computing and organization skills. I would strongly recommend the student to the award, and would appreciate very much of the award in helping him, and me, accomplish this project!)
We plan to publish our results in the Astrophysical Journal (ApJ) or the Monthly Notices of the Royal Astronomical Society (MNRAS) in April 2025. The student will present their poster at the American Astronomical Society (AAS) in January 2025 (first result) and June 2025. In April 2025, we will also present a poster at the 2025 NAU UGRADS symposium as well as the 2025 Arizona Space Grant Symposium. (I would also like to add that this year, 2024, the student’s work with me is all on track in terms of what we planned to achieve. The student went to AAS meeting in 2024 summer, is working on submitting a paper of our work, and several presentations in April. The student has high organization and time management skills that are rarely seen among undergraduate students. I have no doubts that the student will accomplish the outcome of our proposed project as planned. Thank you again for the support in this year, and I’d love to ask you to continue to support the student and share their success to the Space Grant program!)