| Autor: |
N. D. Nevill, P. A. Bland, D. W. Saxey, W. D. A. Rickard, P. Guagliardo, N. E. Timms, L. V. Forman, L. Daly, S. M. Reddy |
| Jazyk: |
angličtina |
| Rok vydání: |
2024 |
| Předmět: |
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| Zdroj: |
The Astrophysical Journal, Vol 964, Iss 2, p 151 (2024) |
| Druh dokumentu: |
article |
| ISSN: |
1538-4357 |
| DOI: |
10.3847/1538-4357/ad2996 |
| Popis: |
We have discovered a presolar olivine from ALH 77307 with the highest ^25 Mg isotopic composition measured in a silicate to date ( δ ^25 Mg = 3025.1‰ ± 38.3‰). Its isotopic compositions challenge current stellar models, with modeling of magnesium, silicon, and oxygen showing a closest match to formation in a supernova (SN) where hydrogen ingestion occurred in the pre-SN phase. Presolar grains within primitive astromaterials retain records of processes and environmental changes throughout stellar evolution. However, accessing these records has proved challenging due to the average grain size (∼150 nm) of presolar silicates, their sensitivity to extraction agents, and instrumental restrictions, limiting the range of isotopic and chemical signatures which can be studied per grain volume. Here, we present the first known detailed geochemical study of a presolar silicate from a hydrogen-burning SN, studied in 3D without contributions to the analysis volume and at unprecedented spatial resolutions ( |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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