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arXiv · 1404.5811

Construction and measurements of a vacuum-swing-adsorption radon-mitigation system

R. W. Schnee·R. Bunker·G. Ghulam·D. Jardin·M. Kos·A. S. Tenney
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Abstract

Long-lived alpha and beta emitters in the $^{222}$Rn decay chain on (and near) detector surfaces may be the limiting background in many experiments attempting to detect dark matter or neutrinoless double-beta decay, and in screening detectors. In order to reduce backgrounds from radon-daughter plate-out onto the wires of the BetaCage during its assembly, an ultra-low-radon cleanroom is being commissioned at Syracuse University using a vacuum-swing-adsorption radon-mitigation system. The radon filter shows ~20$\times$ reduction at its output, from 7.47$\pm$0.56 to 0.37$\pm$0.12 Bq/m$^3$, and the cleanroom radon activity meets project requirements, with a lowest achieved value consistent with that of the filter, and levels consistently < 2 Bq/m$^3$.

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R. W. Schnee, R. Bunker, G. Ghulam, D. Jardin, M. Kos, A. S. Tenney. 2014-04-23. Construction and measurements of a vacuum-swing-adsorption radon-mitigation system. https://doi.org/10.1063/1.4818089

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