2025ApJ...994..187S

A popular solution to the Type Ia supernova (SN Ia) 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 SN Ia, with all tested systems being proven to not have the required red giant: (A) Zero-out-of-nine 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-two normal SN Ia 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)-(D) Zero-out-of-111 normal SN Ia have any detected hydrogen or helium emission lines in their eruption spectra, with limits on entrained gas of M_H < 0.22 and M_He < 0.07 M_⊙, which is the minimum mass lost by a red giant in a nearby blastwave. (E)-(F) Zero-out-of-nine nearby normal SN Ia were detected in the radio or X-rays, as required from the ejecta/wind impact, to limits of ${\dot{M}}_{{\rm{wind}}}\lt 3\times 1{0}^{-9}$M_⊙yr^–1. (G) Zero-out-of-∼69 normal SN Ia 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 SN Ia having any possibility of having a red giant companion, the fraction of SN Ia with symbiotic progenitors is <0.53%. The overwhelming conclusion is that normal SN Ia are not from symbiotic-progenitors in any measurable fraction.