Published December 2, 1983 | Version v1
Journal article

Samarium-146 in the early solar system: evidence from neodymium in the Allende meteorite

  • 1. Univ. of California, San Diego

Description

A carbon-chromite fraction from the Allende C3V chondrite shows strikingly large isotopic enrichments of neodymium-142 (0.47%) and neodymium-143 (36%). Both apparently formed by α decay of samarium-146 and samarium-147 (half-lives 1.03 x 108 and 1.06 x 1011 years), but the isotopic enrichment was greatly magnified by recoil of residual nuclei into a carbon film surrounding the samarium-bearing grains. These data provide an improved estimate of the original abundance of extinct samarium-146 in the early solar system [146Sm/144Sm = (4.5 +/- 0.5) x 10-3], higher than predicted by some models of p-process nucleosynthesis. It may be possible to use this isotopic pair as a chronometer of the early solar system

Additional details

Publishing Information

Journal Title
Science (Washington, D.C.)
Journal Volume
222
Series
Science (Washington, D.C.).
Journal Page Range
1015-1017
ISSN
0036-8075