Velocity-dependent annihilation radiation from dark matter subhalos in cosmological simulations

We use the suite of Milky Way-like galaxies in Auriga simulations to determine contribution annihilation radiation from dark matter subhalos three velocity-dependent models: Sommerfeld, p-wave, and d-wave models. compare these corresponding distribution velocity-independent s-wave model. For both hydrodynamical dark-matter-only simulations, only case Sommerfeld-enhanced does total flux exceed smooth halo component within virial radius halo. Progressing Sommerfeld s, p, models, becomes more dominant, implying that for p-wave models is by far dominant radiation. Comparing Galactic center excess observed Fermi-LAT, all simulated halos emission dominated contribution. However, it possible extrapolation down mass scales below current resolution limit simulation would imply a non-negligible gamma-ray Center region.