|
Nearly three decades ago, two teams of astronomers used a sample of just ~40 Type Ia supernovae (SNe Ia) to reveal a ground-breaking mystery: the accelerating expansion of the Universe. The quest to understand the underlying force (dubbed dark energy) behind this expansion, which currently makes up ~70% of the mass-energy density in our Universe, has captivated the field of modern cosmology ever since. My PhD takes an in-depth look at the SNe Ia modelling underlying all modern SN measurements of dark energy. I apply key updates to existing models, validate new models, develop methods to quantify and reduce underlying systematics within the models, and explore the impact of previously unparameterised host-galaxy relationships in the model framework. The results are presented in the context of the Dark Energy Survey’s 3-Year Supernova Analysis, and directly contribute to the upcoming DES 5-Year SN analysis. |
|