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

Abstract

Abstract We present 2D hydrodynamics simulations of near-Chandrasekhar-mass white dwarf (WD) models for Type Ia supernovae (SNe Ia) using the turbulent deflagration model with a deflagration-to-detonation transition (DDT). We perform a parameter survey for 41 models to study the effects of the initial central density (i.e., WD mass), metallicity, flame shape, DDT criteria, and turbulent flame formula for a much wider parameter space than in earlier studies. The final isotopic abundances of 11C to 91Tc in these simulations are obtained by post-process nucleosynthesis calculations. The survey includes SN Ia models with the central density from 5 × 108 g cm−3 to 5 × 109 g cm−3 (WD masses of 1.30–1.38 M ⊙), metallicity from 0 to 5 Z ⊙, C/O mass ratio from 0.3 to 1.0, and ignition kernels, including centered and off-centered ones. We present the yield tables of stable isotopes from 12Cl to 70Zn, as well as the major radioactive isotopes for 33 models. Observational abundances of 55Mn, 56Fe, 57Fe, and 58Ni obtained from the solar-composition, well-observed SN Ia and SN Ia remnants are used to constrain the explosion models and the SN progenitor. The connection between the pure turbulent deflagration model and the subluminous SNe Iax is discussed. We find that dependencies of the nucleosynthesis yields on the metallicity and the central density (WD mass) are large. To fit these observational abundances, and also for the application of galactic chemical evolution modeling, these dependencies on the metallicity and WD mass should be taken into account.