Dark Matter Decaying into Millicharged Particles as a Solution to AMS 02 Positron Excess

Understand

The positron excess observed by PAMELA and then confirmed by AMS 02 has intrigued the particle physics community since 2008.

• Various dark matter decay and annihilation models have been built to explain the excess.
• However, the bounds from isotropic gamma ray disfavor the canonical dark matter decay scenario.
• We propose a solution to this excess based on the decay of dark matter particles into intermediate millicharged particles which can be trapped by the galactic magnetic field.