EVALUATING SYSTEMATIC DEPENDENCIES OF TYPE Ia SUPERNOVAE: THE INFLUENCE OF PROGENITOR22Ne CONTENT ON DYNAMICS

Abstract

We present a theoretical framework for formal study of systematic effects in Supernovae Type Ia (SN Ia) that utilizes 2-d simulations to implement a form of the deflagration-detonation transition (DDT) explosion scenario. The framework is developed from a randomized initial condition that leads to a sample of simulated SN Ia whose Ni56 masses have a similar average and range to those observed, and have many other modestly realistic features such as the velocity extent of intermediate mass elements. The intended purpose is to enable statistically well-defined studies of both physical and theoretical parameters of the SN Ia explosion simulation. We present here a thorough description of the outcome of the SN Ia explosions produced by our current simulations. A first application of this framework is utilized to study the dependence of the SN Ia on the Ne22 content, which is known to be directly influenced by the progenitor stellar population's metallicity. Our study is very specifically tailored to measure how the Ne22 content influences the competition between the rise of plumes of burned material and the expansion of the star before these plumes reach DDT conditions. This competition controls the amount of material in nuclear statistical equilibrium (NSE) and therefore Ni56 produced by setting the density at which nucleosynthesis takes place during the detonation phase of the explosion. Although the outcome following from any particular ignition condition can change dramatically with Ne22 content, with a sample of 20 ignition conditions we find that the systematic change in the expansion of the star prior to detonation is not large enough to compete with the dependence on initial neutron excess discussed by Timmes, Brown & Truran (2003). (Abridged)