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A Novel Technique for Raman Analysis of Highly Radioactive Samples Using Any Standard Micro-Raman Spectrometer
Published on: April 12, 2017
Radioactive Cs capture in the early solar system
Hiroshi Hidaka1, Shigekazu Yoneda
1Department of Earth and Planetary Systems Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan. hidaka@hiroshima-u.ac.jp
Scientific Reports
|February 26, 2013
Summary
Researchers found excess Barium-135 in early solar system materials, indicating the presence of the extinct radionuclide Cesium-135. This suggests Cesium, including Cesium-135, was remobilized within meteorite parent bodies.
Area of Science:
- Cosmochemistry
- Nuclear Astrophysics
- Planetary Science
Background:
- Barium isotopic compositions in the solar system are typically influenced by s- and r-process nucleosynthesis.
- These processes obscure the isotopic signature of Barium-135, which originates from the decay of Cesium-135.
Purpose of the Study:
- To investigate the isotopic composition of Barium in primitive solar system materials.
- To identify evidence for extinct radionuclides beyond standard nucleosynthetic contributions.
Main Methods:
- Chemical separation of components from Sayama CM2 chondrite chondrules.
- Precise measurement of Barium isotopic abundances.
- Correlation analysis between Barium/Cesium elemental ratios and Barium isotopic excesses.
Main Results:
- An excess of Barium-135 (up to 0.33 ± 0.06%) was detected in chemical separates from Sayama CM2 chondrules.
- This excess was independent of s- and r-process contributions.
- The Barium-135 excess correlated with the Barium-to-Cesium elemental ratio.
Conclusions:
- The findings provide chemical and isotopic evidence for the extinct radionuclide Cesium-135 in the early solar system.
- The estimated abundance of Cesium-135 suggests its production exceeded uniform models, implying remobilization of Cesium within meteorite parent bodies.
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