Explosive Nucleosynthesis in Near-Chandrasekhar-mass White Dwarf Models for Type Iax Supernovae: Dependence on Model Parameters

TL;DR

This study models Type Iax supernovae using 2D hydrodynamical simulations of near-Chandrasekhar-mass white dwarfs, exploring how explosion outcomes depend on various initial parameters and comparing results with observations.

Contribution

It provides a detailed parameter study of SNe Iax using pure turbulent deflagration models, including nucleosynthesis yields and observable predictions, expanding understanding of their diversity.

Findings

Explosion properties vary with initial WD density and composition.

Nucleosynthesis yields depend on flame geometry and turbulence.

Model results match some observed low-mass WDs and SN remnants.

Abstract

The recently observed diversity of Type Ia supernovae (SNe Ia) has motivated us to conduct the theoretical modeling of SNe Ia for a wide parameter range. In particular, the origin of Type Iax supernovae (SNe Iax) has been obscure. Following our earlier work on the parameter dependence of SN Ia models, we focus on SNe Iax in the present study. For a model of SNe Iax, we adopt the currently leading model of pure turbulent deflagration (PTD) of near-Chandrasekhar mass C+O white dwarfs (WDs). We carry out 2-dimensional hydrodynamical simulations of the propagation of deflagration wave, which leaves a small WD remnant behind and eject nucleosynthesis materials. We show how the explosion properties, such as nucleosynthesis and explosion energy, depend on the model parameters such as central densities and compositions of the WDs (including the hybrid WDs), and turbulent flame prescription and initial flame geometry. We extract the associated observables in our models, and compare with the recently discovered low-mass WDs with unusual surface abundance patterns and the abundance patterns of some SN remnants. We provide the nucleosynthesis yield tables for applications to stellar archaeology and galactic chemical evolution. Our results are compared with the representative models in the literature.