The single degenerate channel for the progenitor of type Ia supernovae

TL;DR

This study models the single-degenerate channel for type Ia supernovae progenitors, analyzing binary evolution across metallicities, and estimating birth rates and companion properties to aid observational searches.

Contribution

It provides extensive binary evolution calculations and parameter spaces for SNe Ia progenitors across metallicities, improving understanding of their formation and observable signatures.

Findings

Higher metallicity leads to earlier SNe Ia occurrence and higher peak birth rates.

Galactic birth rate estimates are consistent with observations.

Distributions of binary parameters at explosion aid in companion detection.

Abstract

We have carried out a detailed study of the single-degenerate channel for the progenitors of type Ia supernovae (SNe Ia). In the model, a carbon-oxygen white dwarf (CO WD) accretes hydrogen-rich material from an unevolved or a slightly evolved non-degenerate companion to increase its mass to Chandrasekhar mass limit. Incorporating the prescription of \cite{HAC99a} for the accretion efficiency into Eggleton's stellar evolution code and assuming that the prescription is valid for all metallicities, we performed binary stellar evolution calculations for more than 25,000 close WD binary systems with various metallicities. The initial parameter spaces for SNe Ia are presented in an orbital period-secondary mass ($\log P_{\rm i}, M_{\rm 2}^{\rm i}$) plane for each $Z$. Adopting the results above, we studied the birth rate of SNe Ia for various $Z$ via binary population synthesis. From the study, we see that for a high $Z$, SNe Ia occur systemically earlier and the peak value of the birth rate is larger if a single starburst is assumed. The Galactic birth rate from the channel is lower than (but comparable to) that inferred from observations. We also showed the distributions of the parameters of the binary systems at the moment of supernova explosion and the distributions of the properties of companions after supernova explosion. The former provides physics input to simulate the interaction between supernova ejecta and its companion, and the latter is helpful to search for the companions in supernova remnants.