New Multielement Isotopic Compositions of Presolar SiC Grains: Implications for Their Stellar Origins

@article{Liu2021NewMI,
  title={New Multielement Isotopic Compositions of Presolar SiC Grains: Implications for Their Stellar Origins},
  author={Nan Liu and Jens Barosch and Larry R. Nittler and Conel M O'D Alexander and Jianhua Wang and Sergio Cristallo and Maurizio Busso and Sara Palmerini},
  journal={The Astrophysical Journal Letters},
  year={2021},
  volume={920}
}
We report NanoSIMS Si and Mg–Al isotopic data (and C, N, and Ti isotopic data, when available) for 85 submicron- to micron-sized presolar SiC grains from the CM2 Murchison meteorite, including 60 mainstream (MS), 8 AB1, 8 X, 7 AB2, and 2 Y grains. The MS and Y grain data demonstrate that (1) C and N contamination mainly appears as surface contamination, and sufficient presputtering is needed to expose a clean grain surface for obtaining intrinsic C and N signals, and (2) Mg and Al contamination… 
Oxygen and Aluminum-Magnesium Isotopic Systematics of Presolar Nanospinel Grains from CI Chondrite Orgueil
Presolar oxide grains have been previously divided into several groups (Group 1 to 4) based on their isotopic compositions, which can be tied to several stellar sources. Much of available data was

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TLDR
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