Type Ia supernova ejecta-donor interaction: explosion model comparison

TL;DR

This study compares how two different explosion models of Type Ia supernovae affect the interaction with a main-sequence donor star, focusing on mass stripping and velocity of ejected material, using 2D hydrodynamical simulations.

Contribution

It demonstrates that the choice of explosion model (W7 vs N100) has minimal impact on ejecta-donor interaction outcomes in 2D simulations for normal SNe Ia.

Findings

Approximately 0.30-0.37 solar masses of hydrogen-rich material are stripped.

Donor star receives a kick of about 74-86 km/s.

Stripped material has a modal velocity of 350-500 km/s.

Abstract

In the single-degenerate scenario of Type Ia supernovae (SNe Ia), the interaction between high-speed ejected material and the donor star in a binary system is expected to lead to mass being stripped from the donor. A series of multi-dimensional hydrodynamical simulations of ejecta-donor interaction have been performed in previous studies most of which adopt either a simplified analytical model or the W7 model to represent a normal SN Ia explosion. Whether different explosion mechanisms can significantly affect the results of ejecta-donor interaction is still unclear. In this work, we simulate hydrodynamical ejecta interactions with a main-sequence (MS) donor star in two dimensions for two near-Chandrasekhar-mass explosion models of SNe Ia, the W7 and N100 models. We find that about 0.30 and 0.37 Msun of hydrogen-rich material are stripped from a 2.5 Msun donor star in a 2 day orbit by the SN Ia explosion in simulations with the W7 deflagration and N100 delayed-detonation explosion model, respectively. The donor star receives a kick of about 74 and 86 km/s, respectively, in each case. The modal velocity, about 500 km/s, of stripped hydrogen-rich material in the N100 model is faster than the W7 model, with modal velocity of about 350km/s, by a factor 1.4. Based on our results, we conclude that the choice of near-Chandrasekhar-mass explosion model for normal SNe Ia seems to not significantly alter the ejecta-donor interaction for a given main-sequence donor model, at least in 2D.