Constraint on the velocity dependent dark matter annihilation cross section from gamma-ray and kinematic observations of ultrafaint dwarf galaxies

Understand

Searching for gamma rays from dwarf spheroidal galaxies (dSphs) is a promising approach to detect dark matter (DM) due to the high DM densities and low baryon components in dSphs.

• The Fermi-LAT observations from dSphs have set stringent constraints on the velocity independent annihilation cross section.
• However, the constraints from dSphs may change in velocity dependent annihilation scenarios because of the different velocity dispersions in galaxies.
• In this work, we study how to set constraints on the velocity dependent annihilation cross section from the combined Fermi-LAT observations of dSphs with the kinematic data.