RSAA Colloquia / Seminars / Feast-of-Facts: Thursday, 26 November 2015, 11:00-12:00; Duffield Lecture Theatre

Ivo Seitenzahl

"Modelling thermonuclear supernovae - explosion simulations, nucleosynthesis, observables"

In 2011 the Nobel Prize in Physics was awarded "for the discovery of the accelerating expansion of the Universe through observations of distant supernovae". These Type Ia supernovae (SNe Ia) are also the dominant contributor to iron-group nucleosynthesis and leading candidates for the elusive sites of high energy cosmic rays, the p-process isotopes, and the positrons responsible for the 511 keV annihilation signal in our Galaxy. SNe Ia are thought to be thermonuclear explosions of white dwarf stars. Despite their ubiquitous importance to cosmology and astronomy, their progenitor systems and the explosion mechanism(s) are still largely unknown. This "SN Ia progenitor and explosion mechanism problem" is one of the great unsolved problems in astrophysics, complicated by the fact that in recent years several unique sub-classes of SNe Ia have been described. I will discuss leading explosion models for SNe Ia, present results from multi-dimensional hydrodynamical simulations of the final seconds of the star’s life, and highlight our quest to predict testable observables for the different suggested progenitor and explosion mechanisms of SNe Ia.