Supervisor: Marcel Sven Pawlowski
Introduction to my research
I study dwarf galaxies and satellite galaxies - small galaxies that orbit larger systems such as the Milky Way - and use them as laboratories for testing our understanding of the Universe. My research addresses questions such as: What is dark matter? How do galaxies form and evolve? Do our current theories of gravity and cosmology accurately describe the observed Universe?
My work combines observations, computer simulations, and statistical analysis. I use data from facilities such as the Hubble Space Telescope and the Gaia mission to study the positions, motions, and dynamics of galaxies. I then compare these observations with cosmological simulations and predictions from different models, including cold, warm, and self-interacting dark matter and modified theories of gravity.
A thesis project in my group may involve analyzing observational or simulation data, developing numerical or statistical methods, visualizing galaxy systems, or testing a theoretical prediction. Projects can be adapted to your interests, experience, and preferred balance between physics, programming, and data analysis
Project descriptions
No. 1: “Do different types of dark matter produce different satellite galaxy systems?”
Large galaxies such as the Milky Way are surrounded by smaller satellite galaxies. In standard cold dark matter simulations, these satellites have relatively random positions and motions. Some observed systems, however, are unusually flattened, show signs of coordinated motion, or contain more satellites on one side than the other. In this project, you will use galaxy catalogues from cosmological simulations with alternative dark matter types to compare satellite systems formed with cold, warm, and self-interacting dark matter. You will quantify their shapes and asymmetries and determine whether alternative dark matter models produce systems that more closely resemble observations. The project provides experience with programming, data analysis, statistics, visualization and interpretation of data.
No. 2: “Is there a plane of satellite galaxies around the Large Magellanic Cloud?”
The Milky Way and other massive nearby galaxies have unusually flattened arrangements of satellite galaxies which appear to orbit coherently. Such “planes of satellite galaxies” are rare in cosmological simulations, but it is not yet known whether comparable structures exist around lower-mass galaxies. In this project, you will investigate the satellites of the Large Magellanic Cloud (LMC), the Milky Way’s largest satellite. You will assemble position and velocity data for dwarf galaxies that may be associated with the LMC and examine whether their distribution is unusually flattened or their motions are correlated. By generating mock satellite systems, you will assess the statistical significance of any apparent alignment. If time permits, you may also model the system’s past evolution to explore how interactions with the Milky Way have affected it. The project provides experience with astronomical catalogues, data analysis, statistics, and the visualization and interpretation of galaxy distributions.
No. 3: “What determines the relative velocities of galaxy pairs?”
Observations indicate that pairs of galaxies show a preferred relative velocity of approximately 130–150 km/s. Cosmological simulations produce a similar feature, but its physical origin is not yet understood. In this project, you will investigate what creates this preferred velocity and which physical properties affect its magnitude. Depending on your interests, you could study how it changes over cosmic time, how it depends on galaxy mass or on the physical assumptions used in simulations, or how observational selection affects the result. You could also test whether the velocity distribution can distinguish between dark matter and modified-gravity models. The project will use publicly available observational galaxy catalogs, cosmological simulations and involve programming, statistical data analysis, and the physical interpretation of galaxy dynamics.