Prof. Christopher Reynolds

Clusters of galaxies provide superb laboratories for exploring new particle physics. They represent the most massive dark matter objects in the Universe, making them an important laboratory for probing dark matter decay and annihilation signatures. However, in this talk, I will highlight how the transparency (or lack thereof) of the magnetized intracluster medium (ICM) to X-rays can be a powerful probe of axion-sector physics. I will present new data from the Chandra X-ray Observatory for the Perseus cluster which allows us to set constraints on the existence of low-mass axion-like particles which exceed those possible from the next-generation laboratory and ground-based searches. I shall finish by discussing the future prospects and limitations of these studies.