Evolving to Type Ia Supernovae with Short Delay Times

TL;DR

This paper investigates the WD + He star channel as a progenitor for Type Ia supernovae, showing it can produce SNe Ia with short delay times and contribute to observed rates, linking to young supersoft X-ray sources.

Contribution

It provides a detailed binary population synthesis analysis of the WD + He star channel, highlighting its role in producing short-delay SNe Ia and estimating their Galactic birthrate.

Findings

Galactic SN Ia birthrate from this channel is approximately 0.3×10^{-3} yr^{-1}.

This channel can produce SNe Ia with delay times of 45 million to 140 million years.

WD + He star systems may be related to young supersoft X-ray sources.

Abstract

The single-degenerate model is currently a favourable progenitor model for Type Ia supernovae (SNe Ia). Recent investigations on the WD + He star channel of the single-degenerate model imply that this channel is noteworthy for producing SNe Ia. In this paper we studied SN Ia birthrates and delay times of this channel via a detailed binary population synthesis approach. We found that the Galactic SN Ia birthrate from the WD + He star channel is $\sim 0.3\times 10^{-3} {\rm yr}^{-1}$ according to our standard model, and that this channel can explain SNe Ia with short delay times ($\sim4.5\times10^7 - 1.4\times10^8$ yr). Meanwhile, these WD + He star systems may be related to the young supersoft X-ray sources prior to SN Ia explosions.