Upper limits on DM annihilation cross sections from the first AMS-02 antiproton data

TL;DR

This paper uses AMS-02 antiproton data to set stringent upper limits on dark matter annihilation cross sections above 300 GeV, comparing different cosmic-ray propagation models and dark matter profiles.

Contribution

It provides the first constraints on dark matter annihilation cross sections from AMS-02 antiproton measurements, considering various propagation models and profiles.

Findings

Constraints can be more stringent than gamma-ray limits from dwarf galaxies.

Upper limits vary by a factor of five across different propagation models.

No significant dark matter contribution detected in high-energy antiproton data.

Abstract

The first measurement on the antiproton to proton ratio made by the AMS-02 collaboration agrees with the expection from conventional cosmic-ray secondaries in the kinetic energy range $\sim 10-100$ GeV, which can be turned into stringent upper limits on the dark matter (DM) annihilation cross sections above $\sim 300$ GeV. Using the GALPROP code, we derive the upper limits in various propagation models and DM profiles. We show that in the "conventional" propagation model, for the $q\bar q$, $b\bar b$, and $WW$ final states, the constraints can be more stringent than that derived from the recent Ferm-LAT gamma-ray data on the dwarf spheroidal satellite galaxies. Making use of the typical minimal, median and maximal models obtained from a previous global fit, we show that the variation of the upper limits is around a factor of five. The possibility of DM contribution to the high energy $\bar p/p$ data is discussed.