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arXiv · 1702.01652

Setting a Limit on Anthropogenic Sources of Atmospheric 81Kr through Atom Trap Trace Analysis

J. C. Zappala·K. Bailey·W. Jiang·B. Micklich·P. Mueller·T. P. O'Connor·R. Purtschert
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Abstract

We place a 2.5% limit on the anthropogenic contribution to the modern abundance of 81Kr/Kr in the atmosphere at the 90% confidence level. Due to its simple production and transport in the terrestrial environment, 81Kr (halflife = 230,000 yr) is an ideal tracer for old water and ice with mean residence times in the range of 10^5-10^6 years. In recent years, 81Kr-dating has been made available to the earth science community thanks to the development of Atom Trap Trace Analysis (ATTA), a laser-based atom counting technique. Further upgrades and improvements to the ATTA technique now allow us to demonstrate 81Kr/Kr measurements with relative uncertainties of 1% and place this new limit on anthropogenic 81Kr. As a result of this limit, we have removed a potential systematic constraint for 81Kr-dating.

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J. C. Zappala, K. Bailey, W. Jiang, B. Micklich, P. Mueller, T. P. O'Connor, R. Purtschert. 2017-02-06. Setting a Limit on Anthropogenic Sources of Atmospheric 81Kr through Atom Trap Trace Analysis. https://arxiv.org/abs/1702.01652

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