Young and Massive Binary Progenitors of Type Ia Supernovae and Their Circumstellar Matter

TL;DR

This paper introduces new evolutionary models for Type Ia supernova progenitors that include mass-stripping effects, expanding the potential progenitor parameter space and explaining diverse circumstellar matter observations.

Contribution

The study develops models incorporating mass-stripping effects on companion stars, extending the progenitor parameter space and explaining observed circumstellar matter around SNe Ia.

Findings

Massive MS companions can avoid common envelope formation.

The SN Ia progenitor region extends to donor masses of 6-7 M_sun.

Massive circumstellar matter can explain observations of certain SNe Ia.

Abstract

We present new evolutionary models for Type Ia supernova (SN Ia) progenitors, introducing mass-stripping effect on a main-sequence (MS) or slightly evolved companion star by winds from a mass-accreting white dwarf (WD). The mass-stripping attenuates the rate of mass transfer from the companion to the WD. As a result, quite a massive MS companion can avoid forming a common envelope and increase the WD mass up to the SN Ia explosion. Including the mass-stripping effect, we follow binary evolutions of various WD + MS systems and obtain the parameter region in the initial donor mass - orbital period plane where SNe Ia occur. The newly obtained SN Ia region extends to donor masses of 6-7 M_\sun, although its extension depends on the efficiency of mass-stripping effect. The stripped matter would mainly be distributed on the orbital plane and form very massive circumstellar matter (CSM) around the SN Ia progenitor. It can explain massive CSM around SNe Ia/IIn(IIa) 2002ic and 2005gj as well as tenuous CSM around normal SN Ia 2006X. Our new model suggests the presence of very young (\lesssim 10^8 yr) populations of SNe Ia, being consistent with recent observational indications of young population SNe Ia.