The Core Structure of Presolar Graphite Onions

  title={The Core Structure of Presolar Graphite Onions},
  author={Philip Fraundorf and Martin Wackenhut},
  journal={The Astrophysical Journal},
Of the "presolar particles" extracted from carbonaceous meteorite dissolution residues, i.e., of those particles that show isotopic evidence of formation in the neighborhood of other stars prior to the origin of our solar system, a subset of the onion-like graphite spheres has an interesting concentric graphene core-graphite rim structure. We show here that single graphene sheet defects in the onion cores (e.g., cyclopentane loops) may be observable edge-on by high-resolution electron… 

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