Seminarium "High Energy, Cosmology and Astro-particle Physics (HECA)"

Self-interacting dark matter (SIDM) has been attracting growing interest, since it may solve tensions between naive cold dark matter (CDM) predictions and the observed small-scale structure of the Universe. Observations of dark-matter halos in a wide range of masses, from Milky Way’s dwarf spheroidal galaxies to galaxy clusters, may indicate that the SIDM cross section strongly depends on the velocity. We demonstrate that the indicated velocity dependence is generically realized when the self-scattering saturates the partial-wave Unitarity bound. Saturating the partial-wave Unitarity bound pins down the mass of dark matter as well as the underlying model parameter.More specifically, we consider the gauged Lmu-Ltau model and composite asymmetric dark matter model, and discuss implications for cosmology like the H0 tension and dark matter direct-detection experiments.

https://us02web.zoom.us/j/85478248551