Double-detonation explosions as progenitors of type Iax supernovae

摘要: It has recently been proposed that one sub-class of type Ia supernovae (SNe Ia) is sufficiently both distinct and common to be classified separately from the bulk SNe Ia, with a suggested class name "type Iax supernovae" Iax), after SN 2002cx. We show population properties this can understood if events originate helium double-detonation sub-Chandrasekhar mass explosions, in which carbon--oxygen white dwarf (CO WD) accumulates layer non-degenerate star. have incorporated detailed binary evolution calculations for progenitor systems into synthesis model obtain birthrates delay times such events. The predicted Galactic event rate $\sim$$0.6-1.8\times 10^{-3}\,{\rm yr}^{-1}$, good agreement measured rates Iax. In addition, are $\sim$70\,Myr$-$710\,Myr, consistent fact so far only discovered late-type galaxies. Based on CO WD at explosion previous detonation models, we also estimate distribution resulting brightness ($-13 \gtrsim M_{\rm bol} -19$ mag), reproduce empirical diversity speculate why binaries donor stars might lead similar degenerate donors do not suggest higher necessary ignition lower accretion typically delivered provide explanation.