Dark matter with multiannihilation channels and the AMS-02 positron excess and antiproton data

Abstract

AMS-02 provided the unprecedented statistics in the measurement of the positron fraction from cosmic rays. That may offer a unique opportunity to distinguish the positron spectrum coming from various dark matter (DM) annihilation channels, if DM is the source of this positron excess. Therefore, we consider the scenario that the DM can annihilate into leptonic, quark, and massive gauge boson channels simultaneously with floating branching ratios to test this hypothesis. We also study the impacts from MAX, MED, MIN, and DC diffusion models as well as from isothermal, NFW, and Einasto DM density profiles on our results. We found two parameter regions that can satisfy both AMS-02 $\frac{e^+}{e^++e^-}$ and $\bar{p}/p$ datasets at 95\% CL. i) Under the NFW-MIN combination with $M_{\chi}\subset[10,30]$ TeV. ii) Under the Einasto-DC combination with $M_{\chi}\subset[500,1500]$ GeV.