Galaxy Mass Estimates from Tracer Kinematics

Cosmology tells us that just one quarter of the matter in the Universe is made up of regular baryonic matter. The rest is in the form of dark matter, but the nature of dark matter remains highly uncertain. One key question is how is dark matter distributed inside galaxies? We can’t see dark matter directly, but we can see its effect on visible tracer objects: in particular, it exerts a gravitational pull on objects in the galaxy. So by measuring the motions of these objects, we can work backwards and figure out the mass of dark matter that must be present for them to move in the way they do, and how the mass is distributed. But how well do these dynamical mass estimators perform? How accurate are they? Are they biased? In this project, we have applied mass estimator tools to simulated dwarf galaxies to learn about their performance, which will help us interpret the results when we apply them to real data.