Speaker
Description
The recent infall of the LMC into the Milky Way (MW) has dynamical implications throughout the MW's dark matter halo, leaving an imprint on the MW stellar streams. One way to study the impact of this merger is to use the statistical properties of populations of simulated stellar streams. Using time-evolving MW-LMC simulations described by basis function expansions, I analyse how perturbations to stream properties depend on their radial distance and on-sky location, and assess whether they are driven by the direct stream-LMC interaction and/or the indirect MW halo’s response. In the outer halo, direct stream-LMC encounters increase the fraction of misaligned stream proper motions by ~25%, with the strongest effects aligning with the LMC’s current position. In the inner halo, stream perturbations are dominated by the MW dipole response, though its distinct detectability remains uncertain. Our fiducial MW-LMC model agrees with Dark Energy Survey data, and I predict the fraction of perturbed streams LSST will detect. These measurements will deepen our understanding of dark matter and LMC properties.
