An overview is given of the identified surviving presolar grains in primitive meteorites. Two of these phases are discussed in more detail: (a) Presolar silicon carbide, with special emphasis on heavy element isotopic compositions which trace the slow neutron capture process (s-process) of nucleosynthesis. It is argued that there are problems either with the grain or neutron capture cross section data or with current basic understanding of heavy element nucleosynthesis. (b) Presolar diamonds, where new developments are discussed concerning the origin of the (supernova) Xenon-HL component thought to be contained within them; in addition, arguments are presented in favor of diverse carrier phases for the various Xe components observed in diamond separates.
|Number of pages||12|
|Journal||Proceedings of the Indian Academy of Sciences, Earth and Planetary Sciences|
|Publication status||Published - Dec 1 1998|
- Isotope abundance anomalies
- Presolar grains
ASJC Scopus subject areas
- Earth and Planetary Sciences (miscellaneous)