📝 SummarXiv

Abstract

Type Ia supernovae (SNe) occur when a white dwarf (WD) is disrupted by runaway thermonuclear burning. The nature and observable signatures of the mechanism triggering the explosion are still debated. In this work, we study how supernova remnants (SNRs) are impacted by the `double detonation' explosion mechanism, or a helium shell detonation in a sub-Chandrasekhar WD followed by a core detonation. We evolve double detonation SN models to the remnant phase (up to several centuries) and measure the size of substructures formed in the SNR as a result of turbulent activity. We compare our results to small-scale substructures seen in high-resolution optical observations of the SNR 0509-67.5. Substructures dominated by iron in that SNR are observed to be about $40\%$ larger than those dominated by sulfur. This has been shown to be a definitive signature of the explosion of a sub-Chandrasekhar WD by Mandal et al. Comparisons against our suite of SNR models with a range of core and shell masses suggest that the specific substructure sizes in SNR 0509-67.5 are most consistent with the double detonation explosion of a WD with a carbon-oxygen core mass and a helium shell mass of $1M_{\odot}$ and $>0.05M_{\odot}$, respectively.