Type Ia Supernova Explosions From Hybrid Carbon-Oxygen-Neon White Dwarf Progenitors

Abstract

Motivated by recent results in stellar evolution that predict the existence of hybrid white dwarf (WD) stars with a C–O core inside an O–Ne shell, we simulate thermonuclear (Type Ia) supernovae from these hybrid progenitors. We use the FLASH code to perform multidimensional simulations in the deflagration-to-detonation transition (DDT) explosion paradigm. Our hybrid progenitor models were produced with the MESA stellar evolution code and include the effects of the Urca process, and we map the progenitor model to the FLASH grid. We performed a suite of DDT simulations over a range of ignition conditions consistent with the progenitor’s thermal and convective structure assuming multiple ignition points. To compare the results from these hybrid WD stars to previous results from C–O WDs, we construct a set of C–O WD models with similar properties and similarly simulate a suite of explosions. We find that despite significant variability within each suite, trends distinguishing the explosions are apparent in their Ni 56 yields and the kinetic properties of the ejecta. We compare our results with other recent work that studies explosions from these hybrid progenitors.

Description
Keywords
hydrodynamics, nuclear reactions, nucleosynthesis, abundances, supernovae: general, white dwarfs
Citation
Willcox, D., et al. (2016): Type Ia Supernova Explosions From Hybrid Carbon-OxygenNeon White Dwarf Progenitors. The Astrophysical Journal, 832(1).