Indirect constraints on the dark matter interpretation of excess positrons seen by AMS-02

Abstract

Recently, an excess of high energy positrons in our Galaxy has been observed by AMS-02. The spectrum obtained can be best fitted with the annihilation of $\sim$ TeV dark matter particles. However, recent analysis of Dwarf galaxies by Fermi/LAT observations highly constrains the TeV dark matter annihilation cross-section, and rules out the $b\bar{b}$ and all the leptophilic channels except $4-\mu$ channel. In this article, I show that the remaining possible $4-\mu$ channel is also ruled out by using the observational data from cool-core clusters. Therefore, all the leptophilic channels that can account for the excess positrons seen in AMS-02, HEAT, and PAMELA are ruled out.