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تسجيل مستخدم جديدIdentification of a Jet-Driven Supernova Remnant in the Small Magellanic Cloud: Possible Evidence for the Enhancement of Bipolar Explosions at Low Metallicity
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تأليف
Laura A. Lopez
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Recent evidence has suggested that the supernova remnant (SNR) 0104-72.3 in the Small Magellanic Cloud (SMC) may be the result of a prompt Type Ia SN based on enhanced iron abundances and its association with a star-forming region. In this paper, we present evidence that SNR 0104-72.3 arose from a jet-driven bipolar core-collapse SN. Specifically, we use serendipitous Chandra X-ray Observatory data of SNR 0104-72.3 taken due to its proximity to the calibration source SNR E0102-72.3. We analyze 56 Advanced CCD Imaging Spectrometer (ACIS) observations of SNR 0104-72.3 to produce imaging and spectra with an effective exposure of 528.6 ks. We demonstrate that SNR 0104-72.3 is highly elliptical relative to other nearby young SNRs, suggesting a core-collapse SN origin. Furthermore, we compare ejecta abundances derived from spectral fits to nucleosynthetic yields of Type Ia and core-collapse (CC) SNe, and we find that the iron, neon, and silicon abundances are consistent with either a spherical CC SN of a 18-20 solar mass progenitor or an aspherical CC SN of a 25 solar mass progenitor. We show that the star-formation history at the site of SNR 0104-72.3 is also consistent with a CC origin. Given the bipolar morphology of the SNR, we favor the aspherical CC SN scenario. This result may suggest jet-driven SNe occur frequently in the low-metallicity environment of the SMC, consistent with the observational and theoretical work on broad-line Type Ic SNe and long-duration gamma-ray bursts.
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