Simulating Galactic Dynamo Processes with Smoothed Particle Magnetohydrodynamics

Abstract

When we look out at the universe, we find that magnetic fields are everywhere. From solar flares to the launching of jets, magnetic fields play an important role for a wide range of systems. This includes galaxies, which have been found to host surprisingly strong magnetic fields compared to their predicted strength in the early universe. This means that there must have been significant amplification of the magnetic field during the evolution of these galaxies. But what kind of process could amplify the magnetic field this quickly? Enter magnetic dynamo processes, which describes the exponential growth of magnetic fields due to being stretched, twisted, and folded by the underlying fluid motions. Due to astronomy being an observational science, an important approach to testing astrophysical theories is through the use of numerical simulations. This gives us a ’virtual’ lab to understand how a system will evolve in time. This thesis goes through the development of a new numerical method and its application to the magnetized core-collapse, magneto-rotational instability and galaxy formation. In our simulations of galaxy formation, we find that our new method can capture many of the dynamo processes, recreating the amplification needed to explain our observations.