Evolving to type Ia supernovae with short delay times

Abstract

The single-degenerate model is currently a favorable progenitor model for Type Ia supernovae (SNe Ia). Recent investigations on the white dwarf (WD) + He star channel of the single-degenerate model imply that this channel is noteworthy for producing SNe Ia. In this paper, we studied SNIa birthrates and delay times of this channel via a detailed binary population synthesis approach. We found that the Galactic SNIa birthrate from the WD + He star channel is 0.3 × 10-3 yr-1 according to our standard model, and that this channel can explain SNe Ia with short delay times (4.5 × 10 7-1.4 × 108 yr). Meanwhile, these WD + He star systems may be related to the young supersoft X-ray sources prior to SNIa explosions. © 2009 The American Astronomical Society. All rights reserved.