Plasma Constraints on the Millicharged Dark Matter

TL;DR

This paper establishes new limits on the charge and mass of millicharged dark matter particles by analyzing observational data from the Bullet X-ray Cluster, treating dark matter as a collisionless plasma.

Contribution

It provides the first stringent astrophysical constraints on millicharged dark matter using galaxy cluster observations.

Findings

New upper bounds on the charge of dark matter particles.

Constraints on the mass range of millicharged dark matter.

Implications for dark matter models with small electric charge.

Abstract

Dark matter particles were suggested to have an electric charge smaller than the elementary charge unit $e$. The behavior of such a medium is similar to a collisionless plasma. In this paper, we set new stringent constraints on the charge and mass of the millicharged dark matter particle based on observational data on the Bullet X-ray Cluster.