Uranium Content of Some Stone Meteorites and their Pu–Xe Decay Interval

Abstract

Kuroda and Reynolds have recently discussed whether or not the Pu–Xe and I–Xe decay intervals of stone meteorites are concordant, and the implications of this question to models of galactic nucleosynthesis. Kuroda states^1,2 that they are concordant, while Reynolds^3,4 believes the question is still open. Kuroda notes that the ^136fXe/U ratios are excessively high in two eucrites, Petersburg and Moore County, indicating Pu–Xe decay intervals for these two meteorites which are not concordant with their I–Xe decay intervals beyond his acceptable limits of error (± 30 per cent). Using his average eucrite uranium abundance of 130 p.p.b. for these two meteorites, instead of their measured abundances of 100 and 40 p.p.b. respectively, he brings the decay intervals to near concordancy, arguing that the measured uranium abundances may well be wrong because of tellurium interferences with the neutron activation analysis. It therefore becomes a critical test of Kuroda's model to measure the uranium in either of these meteorites by a different technique. In particular, the difference between the measured and predicted U abundances in Moore County is significant.