The Core Structure of Presolar Graphite Onions
نویسندگان
چکیده
منابع مشابه
The Core Structure of Presolar Graphite Onions
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 ...
متن کاملOn the stellar sources of presolar graphite
Primitive meteorites contain graphite spherules whose anomalous isotopic compositions indicate a stellar origin. The isolation of presolar graphite grains is difficult and they have been less well studied than presolar silicon carbide grains. While previous isotopic measurements have been made on graphite from the Murchison meteorite and mostly on low-density grains, a new separation of graphit...
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Introduction: Presolar graphite grains were first isolated from the Murchison (CM2) meteorite by [1]. Analysis of their major and trace element isotopic compositions indicates that they are condensates from AGB-stars, Wolf-Rayet stars and Type II Supernovae [2-4]. To date all studies of presolar graphite have been carried out on grains extracted using acid dissolution techniques [5,6]. Recent e...
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15 صفحه اولPresolar Graphite from the Murchison Meteorite: Noble Gases Revisited
Introduction: Ne-E(L) is one of the anomalous noble gas components that ultimately led to the discovery of presolar grains in meteorites. The component is extremely enriched in 22 Ne and this fact prompted the idea that the 22 Ne is from the decay of 22 Na [1]. The carrier of Ne-E(L) is presolar graphite [2], which has been extracted from Murchison [3] and Orgueil [4]. There are four graphite-r...
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ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2002
ISSN: 0004-637X,1538-4357
DOI: 10.1086/344633