![](https://astro.unistra.fr/wp-content/uploads/2025/02/Arabsalmani_etal_Filament_PR-Fig1_white_scales-300x225.png)
Probing substructure with cold stellar streams: the diffusion regime
Abstract
Cold tidal streams from disrupting globular clusters offer a promising probe to constrain substructure (small-scale potential perturbations) in the Milky Way halo, purely gravitationally. While the bulk of the literature has focused on strong perturbations (« gaps »), I will present a new approach to describing the stream-substructure interaction, which considers the much more prevalent weak stream perturbations. This approach allows us to directly and semi-analytically predict statistics such as the one-dimensional power spectrum of stellar density and velocity along the stream