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DOE OSTI · 1756423

Enhanced detection limits for radiokrypton analysis

Zappala, Jake C.·McLain, Derek·Mueller, Peter·Steeb, Jennifer L.
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Abstract

In this paper, we present a method for improving detection limits of Atom Trap Trace Analysis for the krypton radioisotopes 85 Kr and 81 Kr. For the case of 85 Kr this work demonstrates that systematic use of isotopically depleted gas for calibration and extended conditioning of the instrument results in a detection limit of 900 85 Kr atoms per 11 μl of Kr gas, equivalent to a 85 Kr/Kr isotopic abundance of 3 x 10 -15 . This improvement of roughly two orders of magnitude over previously reported limits will help to expand the reach of radiokrypton dating towards longer age ranges where most of the radioisotopes have decayed. Additionally, the method offers an opportunity to investigate radiokrypton production via spontaneous fission within naturally occurring minerals to understand potential underground production of these isotopes.

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38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRYatom trap trace analysisgroundwater datingradiokrypton

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Zappala, Jake C., McLain, Derek, Mueller, Peter, Steeb, Jennifer L.. 2020-09-21. Enhanced detection limits for radiokrypton analysis. https://doi.org/10.1007/s10967-020-07355-7

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