Dark matter powered stars: Constraints from the extragalactic background light

TL;DR

This paper investigates how dark matter powered stars, or dark stars, could contribute to the extragalactic background light and uses existing data to constrain their properties, providing new insights into dark matter's role in early stellar evolution.

Contribution

It introduces a method to constrain dark matter powered stars using extragalactic background light measurements, linking dark matter properties with observable cosmic radiation.

Findings

Existing EBL data can rule out some dark star models.

Dark matter annihilation in stars affects their evolution and emission.

Constraints on dark matter properties from diffuse background observations.

Abstract

The existence of predominantly cold non-baryonic dark matter is unambiguously demonstrated by several observations (e.g., structure formation, big bang nucleosynthesis, gravitational lensing, and rotational curves of spiral galaxies). A candidate well motivated by particle physics is a weakly interacting massive particle (WIMP). Self-annihilating WIMPs would affect the stellar evolution especially in the early universe. Stars powered by self-annihilating WIMP dark matter should possess different properties compared with standard stars. While a direct detection of such dark matter powered stars seems very challenging, their cumulative emission might leave an imprint in the diffuse metagalactic radiation fields, in particular in the mid-infrared part of the electromagnetic spectrum. In this work the possible contributions of dark matter powered stars (dark stars; DSs) to the extragalactic background light (EBL) are calculated. It is shown that existing data and limits of the EBL intensity can already be used to rule out some DS parameter sets.