Large Ca-48 anomalies are associated with Ti-50 anomalies in Murchison and Murray hibonites
Ion microprobe measurements of the Ca isotopic compositions of eight individual hibonite grains from the Ca chondrites Murray and Murchison are reported. Large Ca-48 anomalies two orders of magnitude larger than those observed in normal inclusions and at least a factor of four larger than in the FUN inclusions are found. These anomalies are qualitatively correlated with the Ti-50 anomalies in the sense that the delta Ca-48 and delta Ti-50 values have the same sign. These results confirm previous conclusions concerning the presence of a nucleosynthetic component produced by neutron-rich nuclear statistical equilibrium processes. They suggest the preservation of the isotopic anomalies with interstellar dust grains as carriers of the n-rich Ca and Ti components. The large variation in the delta Ca-48/delta Ti-50 ratios indicates multiple nucleosynthetic components and/or chemical fractionation between Ca and Ti prior to hibonite formation. 29 references.
- Research Organization:
- Washington Univ., Saint Louis, MO; Physical Research Lab., Ahmedabad, India; Australian National Univ., Canberra
- OSTI ID:
- 6541321
- Journal Information:
- Astrophys. J.; (United States), Vol. 311
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
GENERAL PHYSICS
CHONDRITES
ISOTOPE RATIO
ABUNDANCE
CALCIUM ISOTOPES
CHEMICAL COMPOSITION
INTERSTELLAR GRAINS
ION MICROSCOPES
NUCLEOSYNTHESIS
SOLAR SYSTEM
TITANIUM ISOTOPES
ALKALINE EARTH ISOTOPES
ISOTOPES
METEORITES
MICROSCOPES
PARTICLES
STONE METEORITES
SYNTHESIS
640107* - Astrophysics & Cosmology- Planetary Phenomena