DeCAF Seminar Series:

Abstract: Dark matter constitutes the majority of the matter content of the Universe, yet its fundamental properties remain unknown. Its presence is inferred through its gravitational effects on cosmic structures of all scales. Galaxy clusters are the most massive gravitationally bound structures in the Universe, with extremely high dark matter densities, making them ideal environments to probe the nature of dark matter. For example, if dark matter particles can interact with each other, this could lead to visible effects such as shifts between gas and dark matter during collisions, rounder galaxy cluster shapes, the loss of smaller substructures, and changes to the density distribution of objects. In this talk I will introduce some of the evidence for dark matter and the ways we are trying to find it, and present my work studying the effects of self-interacting dark matter using computer simulations of galaxy clusters.

Speaker Bio: Dr. Ellen Sirks received her PhD in 2022 from Durham University under the supervision of Prof. Richard Massey and Prof. Carlos Frenk. Since then, she has been working as a research associate in the Astroparticle Physics group, led by Prof. Celine Boehm, at the University of Sydney. Her research focuses on using cosmological hydrodynamical simulations of galaxy clusters to probe the nature of dark matter. In addition to her simulation work, she contributes to SuperBIT, a balloon-borne optical telescope, assisting with data analysis and the design of the data retrieval package, which enables mid-flight data retrieval. She will join us as a JdC fellow at UAM soon.