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arXiv · 2309.15093

Point-symmetry in SNR G1.9+0.3: A supernova that destroyed its planetary nebula progenitor

Noam Soker
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Abstract

I analyze a new X-ray image of the youngest supernova remnant (SNR) in the Galaxy, which is the type Ia SNR G1.9+0.3, and reveal a very clear point-symmetrical structure. Since explosion models of type Ia supernovae (SNe Ia) do not form such morphologies, the point-symmetrical morphology must come from the circumstellar material (CSM) into which the ejecta expands. The large-scale point-symmetry that I identify and the known substantial deceleration of the ejecta of SNR G1.9+0.3 suggest a relatively massive CSM of >1Mo. I argue that the most likely explanation is the explosion of this SN Ia into a planetary nebula (PN). The scenario that predicts a large fraction of SN Ia inside PNe (SNIPs) is the core degenerate scenario. Other SN Ia scenarios might lead to only a very small fraction of SNIPs or not at all.

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Noam Soker. 2023-09-26. Point-symmetry in SNR G1.9+0.3: A supernova that destroyed its planetary nebula progenitor. https://arxiv.org/abs/2309.15093

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