Speaker
Description
The nature of supernova (SN) explosions can be unveiled by the geometry of their remnants. We develop a systematic machine-learning–based framework to analyze the geometric structures of supernova remnants (SNRs). By applying Gaussian Mixture Model (GMM) fitting to the observed brightness distributions, we decompose both the shock fronts and interior materials into multiple Gaussian components, characterizing the structural features imprinted by the SN explosion. This paper presents the first application of this method to assess the explosion center of an SNR. We apply this approach to the Type Ia SNR 0548–70.4 in the Large Magellanic Cloud, derive an explosion site, and quantify its associated positional uncertainty. Using these results, we conduct a refined search for surviving companions of Type Ia SN progenitors within SNR 0548–70.4. Building upon our previous studies, we incorporate updated evolutionary models of surviving red-giant (RG) companions, thereby better constraining the companion candidates to about 20 RG stars. Furthermore, we estimate the mass of the circumstellar medium within SNR 0548–70.4 to have a lower limit of 0.18--0.38 $M_\odot$, assuming a filling factor of 1. Under this condition, we conclude that if SNR 0548–70.4 originated from a single-degenerate system, the surviving companion of its SN progenitors is most likely a RG or a post-He-flash RG. Main-sequence companions are excluded under the standard Chandrasekhar mass explosions. Future spectroscopic observations would help constrain whether these 20 RG stars are surviving companions of the SN's progenitors.
| Participate the oral/poster presentation award competition | No |
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