Isotope studies of presolar silicon carbide grains from supernovae

• Verfasst von: Hoppe, Peter [VerfasserIn]
• Verfasst von: Leitner, Jan [VerfasserIn]
• Verfasst von: Pignatari, Marco [VerfasserIn]
• Verfasst von: Amari, Sachiko [VerfasserIn]
• Titel: Isotope studies of presolar silicon carbide grains from supernovae
• Titelzusatz: new constraints for hydrogen-ingestion supernova models
• Verf.angabe: Peter Hoppe, Jan Leitner, Marco Pignatari and Sachiko Amari
• E-Jahr: 2024
• Jahr: July 2024
• Umfang: 12 S.
• Illustrationen: Illustrationen
• Fussnoten: Veröffentlicht: 19 June 2024 ; Gesehen am 17.01.2025
• Titel Quelle: Enthalten in: Royal Astronomical SocietyMonthly notices of the Royal Astronomical Society
• Ort Quelle: Oxford : Oxford Univ. Press, 1827
• Jahr Quelle: 2024
• Band/Heft Quelle: 532(2024), 1 vom: Juli, Seite 211-222
• ISSN Quelle: 1365-2966
• DOI: doi:10.1093/mnras/stae1523
• Datenträger: Online-Ressource
• Sprache: eng
• K10plus-PPN: 1914939972

Abstract

We report isotope data for C, N, Al, Si, and S of 33 presolar SiC and Si3N4 grains (0.3-1.6 $\mu$m) of Type X, C, D, and N from the Murchison CM2 meteorite of likely core-collapse supernova (CCSN) origin which we discuss together with data of six SiC X grains from an earlier study. The isotope data are discussed in the context of hydrogen ingestion supernova (SN) models. We have modified previously used ad-hoc mixing schemes in that we considered (i) heterogeneous H ingestion into the He shell of the pre-SN star, (ii) a variable C-N fractionation for the condensation of SiC grains in the SN ejecta, and (iii) smaller mass units for better fine-tuning. With our modified ad-hoc mixing approach over small scales (0.2-0.4 M⊙), with major contributions from the O-rich O/nova zone, we find remarkably good fits (within a few per cent) for 12C/13C, 26Al/27Al, and 29Si/28Si ratios. The 14N/15N ratio of SiC grains can be well matched if variable C-N fractionation is considered. However, the Si3N4 isotope data point to overproduction of 15N in hydrogen ingestion CCSN models and lower C-N fractionation during SiC condensation than applied here. Our ad-hoc mixing approach based on current CCSN models suggests that the O-rich O/nova zone, which uniquely combines explosive H- and He-burning signatures, is favourable for SiC and Si3N4 formation. The effective range of C/O abundance variations in the He shell triggered by H ingestion events in the massive star progenitor is currently not well constrained and needs further investigation.