Diffuse $\gamma$-rays and $\bar{p}$ flux from dark matter annihilation -- a model for consistent results with EGRET and cosmic ray data

TL;DR

This paper presents a new cosmic ray propagation model incorporating dark matter annihilation, successfully matching gamma-ray and cosmic ray data from multiple sources and improving previous models by including subhalo contributions and supernova remnant distributions.

Contribution

The model integrates dark matter annihilation into GALPROP, accounts for subhalo boosts, and aligns gamma-ray and cosmic ray observations more accurately than prior models.

Findings

Compatible gamma-ray spectra with EGRET data across the sky

Consistent cosmic ray spectra including B/C and antiprotons

Improved gamma-ray fit using supernova remnant source distribution

Abstract

In this work we develop a new propagation model for the Galactic cosmic rays based on the GALPROP code, including contributions from dark matter annihilation. The model predicts compatible Galactic diffuse $\gamma$ ray spectra with EGRET data in all sky regions. It also gives consistent results of the diffuse $\gamma$ ray longitude and latitude distributions. Further the results for B/C, $^{10}$Be/$^9$Be, proton, electron and antiproton spectra are also consistent with cosmic ray measurements. In the model we have taken a universal proton spectrum throughout the Galaxy without introducing large fluctuation for the proton energy loss is negligible. The dark matter annihilation signals are `boosted' after taking the contribution from subhalos into account. Another interesting feature of the model is that it gives better description of the diffuse $\gamma$ rays when taking the source distribution compatible with supernova remnants data, which is different from previous studies.