p-wave Annihilating Dark Matter from a Decaying Predecessor and the Galactic Center Excess

Understand

Dark matter (DM) annihilations have been widely studied as a possible explanation of excess gamma rays from the galactic center seen by Fermi/LAT.

• However most such models are in conflict with constraints from dwarf spheroidals.
• Motivated by this tension, we show that p-wave annihilating dark matter can easily accommodate both sets of observations due to the lower DM velocity dispersion in dwarf galaxies.
• Explaining the DM relic abundance is then challenging.