Addressing $\gamma$-ray emissions from dark matter annihilations in 45 milky way satellite galaxies and in extragalactic sources with particle dark matter models

TL;DR

This paper investigates gamma-ray emissions from dark matter annihilations in 45 Milky Way dwarf galaxies and extragalactic sources, comparing theoretical flux predictions with observational data to constrain dark matter models.

Contribution

It provides a detailed analysis of gamma-ray fluxes from dark matter annihilation in multiple dwarf galaxies using various density profiles and compares these with observational bounds.

Findings

Constraints on dark matter models based on gamma-ray flux limits.

Different density profiles significantly affect flux predictions.

Extended analysis to extragalactic gamma-ray flux upper bounds.

Abstract

The mass to luminosity ratio of the dwarf satellite galaxies in the Milky Way suggests that these dwarf galaxies may contain substantial dark matter. The dark matter at the dense region such as within or at the vicinity of the centres of these dwarf galaxies may undergo the process of self annihilation and produce $\gamma$-rays as the end product. The satellite borne $\gamma$-ray telescope such as Fermi-LAT reported the detection of $\gamma$-rays from around 45 Dwarf Spheroidals (dSphs) of Milky Way. In this work, we consider particle dark matter models described in the literature and after studying their phenomenologies, we calculate the $\gamma$-ray fluxes from the self annihilation of the dark matter within the framework of these models in case of each of these 45 dSphs. we then compare the computed results with the observational upper bounds for $\gamma$-ray flux reported by Fermi-LAT and Dark Energy Survey (DES) for each of the 45 dSphs. The fluxes are calculated by adopting different dark matter density profiles. We then extend similar analysis for the observational upper bounds given by Fermi-LAT for the continuum $\gamma$-ray fluxes originating from extragalactic sources.