A comprehensive progenitor model for SNe Ia

Abstract

Incorporating the effect of mass-stripping and accretion-disk instability on the evolution of WD binary, we carried out binary stellar evolution calculations for more than 1600 close WD binaries. As a result, 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. We confirmed that in a WD + MS system, the initial companion leading to SNe Ia may have mass from 1 $M_{\odot}$ to 5 $M_{\odot}$. The initial WD mass for SNe Ia from WD + MS channel is as low as 0.565 $M_{\odot}$, while the lowest WD mass from the WD + RG channel is 1.0 $M_{\odot}$. Adopting the results above, we studied the birth rate of SNe Ia via a binary population synthesis approach. We found that the Galactic SNe Ia birth rate from SD model is $2.55 - 2.9\times10^{\rm -3}$ ${\rm yr}^{\rm -1}$ (including WD + He star channel), which is slightly smaller than that from observation. If a single starburst is assumed, the distribution of the delay time of SNe Ia from the SD model is a weak bimodality, where WD + He channel contribute to SNe Ia with delay time shorter than $10^{\rm 8}$ yr and WD + RG channel to those with age longer than 6 Gyr.