Special KICP seminar: Sophia Lilleengen (Surrey/CCA)

12:00–1:00 pm ERC 401

Sophia Lilleengen (Surrey/CCA) "The effect of dark matter deformations of the Milky Way and the Large Magellanic Cloud on the Orphan-Chenab stream"

The ongoing merger of the Milky Way and the Large Magellanic Cloud (LMC) is deforming the dark matter haloes of both galaxies, effectively making these galaxies a local dark matter collider. Within this collider, stellar streams act as useful detectors as they are very sensitive to the gravitational potential, and span large parts of the Milky Way halo. The Orphan-Chenab (OC) stream is particularly insightful as it spans the inner and outer Milky Way, and it passes close to the LMC. To model OC successfully, it is necessary to include the LMC and the reflex motion of the Milky Way induced by the LMC. In this talk, I will present the first models of the OC stream in the time-dependent halos of the Milky Way and the LMC that are described by basis function expansions of N-body simulations of the Milky Way-LMC passage. I will show how these deformations have an observable signature on the OC stream. In particular, we find that the Milky Way’s dipole has the most significant effect. This is a promising first step using stellar streams as detectors in this dark matter collider to test the collisionless nature of dark matter.

Event Type


Jun 9