Exact progenitors and explosion mechanisms of Type Ia supernovae

Determine the exact details of the progenitor scenarios and explosion mechanisms that produce Type Ia supernovae, including specifying the physical conditions and pathways under which single-degenerate, double-degenerate, or higher-multiplicity systems lead to the thermonuclear disruption of carbon–oxygen white dwarfs.

Background

The paper investigates the nebular-phase mid-infrared spectrum of SN 2021aefx with JWST/MIRI and interprets the observations using delayed-detonation models near the Chandrasekhar mass. Despite progress for this particular event, the broader astrophysical question of the exact progenitor channels and explosion mechanisms for Type Ia supernovae remains unsettled across the population.

The authors review leading scenarios (single-degenerate vs. double-degenerate, and multiple-star systems) and explosion mechanisms (near-Chandrasekhar mass delayed detonation vs. sub-Chandrasekhar detonations), emphasizing their complex interplay and the importance of resolving this uncertainty for nucleosynthesis and cosmological applications.