Dark matter annihilation into four-body final states and implications for the AMS antiproton excess

2018 American Physical Society. We consider dark matter annihilation into a general set of final states of standard model particles, including two-body and four-body final states that result from the decay of intermediate states. For dark matter masses 10-105 GeV, we use updated data from Planck and from high gamma-ray experiments such as Fermi-LAT, MAGIC, and VERITAS to constrain the annihilation cross section for each final state. The Planck constraints are the most stringent over the entire mass range for annihilation into light leptons, and the Fermi-LAT constraints are the most stringent for four-body final states up to masses 104 GeV. We consider these constraints in light of the recent AMS antiproton results, and show that for light mediators it is possible to explain the AMS data with dark matter, and remain consistent with Fermi-LAT Inner Galaxy measurements, for m60-100 GeV mass dark matter and mediator masses m/m1.

Dark matter annihilation into four-body final states and implications for the AMS antiproton excess Academic Article