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arXiv · 2511.19948

Symbiotic Stars (Including T Corona Borealis) Are Not Immediate Progenitors of Normal Type Ia Supernovae

Abstract

A popular solution to the Type Ia supernova (SNIa) progenitor problem is that the immediate progenitors are symbiotic star systems. This solution requires that the companion star of the exploding white dwarf must be a red giant star with a heavy stellar wind. This has been tested for 189 normal SNIa, with all tested systems being proven to not have the required red giant: (A) Zero-out-of-9 normal type Ia supernova remnants have any red giant ex-companion star near the center with limits of $M_V$$>$0.0. (B) Zero-out-of-2 normal SNIa in nearby galaxies have any red giant at the position as seen in archival pre-eruption images by HST to limits of $M_V$$>$0.0. (C and D) Zero-out-of-111 normal SNIa have any detected hydrogen or helium emission lines in their eruption spectra, with limits on entrained gas of $M_{\rm H}$$<$0.22 and $M_{\rm He}$$<$0.07 M$_{\odot}$, which is the minimum mass lost by a red giant in a nearby blastwave. (E and F) Zero-out-of-9 nearby normal SNIa were detected in the radio or X-rays, as required from the ejecta/wind impact, to limits of $\dot{M}_{\rm wind}$$<$3$\times$$10^{-9}$ M$_{\odot}$ yr$^{-1}$. (G) Zero-out-of-$\sim$69 normal SNIa display any brightening in the first few days to limits of $M_V$$>$$-$18, as required for a red giant companion when we are looking down its shadowcone. With zero-out-of-189 normal SNIa having any possibility of having a red giant companion, the fraction of SNIa with symbiotic progenitors is $<$0.53%. The overwhelming conclusion is that normal SNIa are not from symbiotic-progenitors in any measurable fraction.

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BibTeXRIS

Bradley E. Schaefer. 2025-11-25. Symbiotic Stars (Including T Corona Borealis) Are Not Immediate Progenitors of Normal Type Ia Supernovae. https://arxiv.org/abs/2511.19948

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