Challenging the 'cold' and 'collisionless' nature of dark matter on small astrophysical scales with the Milky Way satellite galaxies

Milky Way (MW) satellite galaxies, some of the faintest and most dark matter (DM)-dominated systems, offer unique insights into DM properties at small astrophysical scales. This work employs a forward-modeling framework to investigate how DM microphysics influences MW satellite characteristics. By exploring scenarios of warm DM (WDM) and self-interacting DM (SIDM), we analyze the satellites' abundance, galaxy-halo connection, tidal evolution, and density profiles. Our model simulates a joint distribution of satellite luminosities (M_V) and velocity dispersions (σ_∗) under these DM paradigms, extracting constraints on DM particle mass, cross-section, and MW satellite structure through Bayesian statistical inference. Results reveal interesting forecasts on DM properties which could potentially be observable with next-generation surveys, such as the Rubin Observatory.