Alessandro Dondarini (GGI Firenze)

Updated Indirect Detection Constraints on Minimal Dark Matter

Minimal Dark Matter represents one of the simplest and most predictive dark matter frameworks, with the Majorana SU(2) 5-plet being its smallest accidentally stable real representation. In this talk, I will present a detailed reassessment of its indirect-detection signals. The gamma-ray flux from both Sommerfeld-enhanced annihilations and bound state formation is computed, including next-to-leading-order corrections and next-to-leading-log resummation of the relevant electroweak effects. In the Milky Way halo, bound state formation is found to dominate the flux in the hundreds of GeV range. The corresponding low-energy spectrum is used to derive constraints from Fermi-LAT observations of Galactic diffuse emission, while the high-energy component is employed to forecast the required observation time for several of the Milky Way’s dwarf spheroidal galaxies with the Cherenkov Telescope Array Observatory (CTAO). Fermi-LAT data strongly disfavor the lower edge of the thermal mass window, even under conservative assumptions about the inner Galaxy density profile. Finally, I will discuss how several hundred hours of forthcoming CTAO observations of northern dwarfs should be sufficient to probe the central mass value.