Supernovae (SNe) are the universe's most energetic explosions, playing a vital role in galaxy evolution and building up the universe's chemical composition. Type Ia SNe, arising from the thermonuclear explosion of white dwarfs (WDs) (either through accretion or merger), are crucial as "standard candles" for accurate cosmic distance measurement; they were used to discover the universe's accelerated expansion. Despite their importance, the exact origins of Type Ia SNe remain debated. Furthermore, large SN surveys have revealed a wide variety of non-standard, peculiar SNe sub-types. Although these lack the standardizability of normal Ia's, their estimated rates are comparable, and they are important for chemical evolution. Their unique properties open new questions that likely hold clues to the origins of all thermonuclear SNe. In this ERC project, we explored all types of thermonuclear explosions of WDs producing both "normal" and peculiar SNe, developing novel explosion models to explain their origin and relate them directly to observations. We used extensive simulations to explore a large phase space of initial conditions (including hybrid WDs and the role of Helium) and formation channels, such as Neutron Star–White Dwarf (NS–WD) mergers. Simulation results were followed using radiative transfer codes to provide detailed predictions for observable properties (light-curve, spectra, chemical composition). We also explored expected rates and host environments to link our theoretical models to observed peculiar SNe families.
Understanding the origin of such SNe is a crucial part of our understanding of the evolution of the universe, the origin of the elements, and essentially trying to answer key issues about the universe at large.
