TAPIR Seminar

In person: 370 Cahill. To Join via Zoom: 868 5298 8404

ABSTRACT: Stellar streams are the remnants of dwarf galaxies and globular clusters that become tidally disrupted around a host galaxy. The morphology and dynamics of the resulting tidal tails encode information about the gravitational potential. In this talk, I will present new methods and results for using streams as dark matter detectors across orders of magnitude in mass scales. I will discuss how the 6D phase-space track of a stream can be used to measure the local galactic acceleration field, and extend this approach to extragalactic streams, where only the morphology of a stream is typically observable. These techniques constrain the smooth distribution of dark matter in a halo. I will then introduce a new GPU accelerated code for modeling streams in different dark matter subhalo environments, and present constraints on the subhalo mass function derived from the velocity dispersion and density structure of the GD-1 stream. Together, these methods constrain the nature of dark matter from the scale of the stellar halo down to subhalos.