How to search for Mirror Stars with Gaia

TL;DR

This paper proposes a novel method to search for mirror stars, a form of dark matter, using Gaia data, and demonstrates its potential to constrain their properties through a detailed pipeline and initial search results.

Contribution

It introduces the first detailed pipeline for detecting mirror stars with Gaia data and provides projected bounds on their abundance if none are found.

Findings

Developed a pipeline for mirror star detection using Gaia data.

Performed a search for toy mirror stars with simplified emission models.

Projected exclusion bounds on mirror star properties based on non-detections.

Abstract

We show for the first time how to conduct a direct search for dark matter using Gaia observations. Its public astrometric data may contain the signals of mirror stars, exotic compact objects made of atomic dark matter with a tiny kinetic mixing between the dark and SM photon. Mirror stars capture small amounts of interstellar material in their cores, leading to characteristic optical/IR and X-ray emissions. We develop the detailed pipeline for conducting a mirror star search using data from Gaia and other stellar catalogues, and demonstrate our methodology by conducting a search for toy mirror stars with a simplified calculation of their optical/IR emissions over a wide range of mirror star and hidden sector parameters. We also obtain projected exclusion bounds on the abundance and properties of mirror stars if no candidates are found, demonstrating that Gaia is a new and uniquely powerful probe of atomic dark matter. Our study provides the blueprint for a realistic mirror star search that includes a more complete treatment of the captured interstellar gas in the future.