Dark Matter with multi-annihilation channels and AMS-02 positron excess and antiproton

TL;DR

This paper investigates dark matter annihilation channels as the source of the AMS-02 positron excess, analyzing various models and density profiles to identify parameter regions consistent with observational data.

Contribution

It introduces a multi-channel dark matter annihilation model with variable branching ratios and evaluates its compatibility with cosmic ray data under different astrophysical assumptions.

Findings

Identified two parameter regions consistent with AMS-02 positron and antiproton data.

Demonstrated the impact of different density profiles and diffusion models on dark matter constraints.

Provided mass ranges for dark matter particles compatible with observations.

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.