Constraining particle dark matter using local galaxy distribution

TL;DR

This paper uses gamma-ray observations and galaxy distribution data to place stringent constraints on TeV-scale decaying dark matter models, effectively excluding those proposed to explain recent cosmic-ray excesses.

Contribution

It introduces a novel method of constraining dark matter properties through cross-correlation of gamma rays with local galaxy distribution, considering recent astrophysical modeling advances.

Findings

Gamma-ray inverse-Compton emission imposes strong constraints on TeV dark matter.

Decaying dark matter models explaining cosmic-ray excesses are excluded.

Constraints on annihilating dark matter scenarios are also discussed.

Abstract

It has been long discussed that cosmic rays may contain signals of dark matter. In the last couple of years an anomaly of cosmic-ray positrons has drawn a lot of attentions, and recently an excess in cosmic-ray anti-proton has been reported by AMS-02 collaboration. Both excesses may indicate towards decaying or annihilating dark matter with a mass of around 1-10 TeV. In this article we study the gamma rays from dark matter and constraints from cross correlations with distribution of galaxies, particularly in a local volume. We find that gamma rays due to inverse-Compton process have large intensity, and hence they give stringent constraints on dark matter scenarios in the TeV scale mass regime. Taking the recent developments in modeling astrophysical gamma-ray sources as well as comprehensive possibilities of the final state products of dark matter decay or annihilation into account, we show that the parameter regions of decaying dark matter that are suggested to explain the excesses are excluded. We also discuss the constrains on annihilating scenarios.