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arXiv · 1708.08535

Radon Mitigation for the SuperCDMS SNOLAB Dark Matter Experiment

J. Street·R. Bunker·E. H. Miller·R. W. Schnee·S. Snyder·J. So
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Abstract

A potential background for the SuperCDMS SNOLAB dark matter experiment is from radon daughters that have plated out onto detector surfaces. To reach desired backgrounds, understanding plate-out rates during detector fabrication as well as mitigating radon in surrounding air is critical. A radon mitigated cleanroom planned at SNOLAB builds upon a system commissioned at the South Dakota School of Mines & Technology (SD Mines). The ultra-low radon cleanroom at SD Mines has air supplied by a vacuum-swing-adsorption radon mitigation system that has achieved $>$1000$\times$ reduction for a cleanroom activity consistent with zero and $<0.067\,$Bq$\,$m$^{-3}$ at 90% confidence. Our simulation of this system, validated against calibration data, provides opportunity for increased understanding and optimization for this and future systems.

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J. Street, R. Bunker, E. H. Miller, R. W. Schnee, S. Snyder, J. So. 2017-08-28. Radon Mitigation for the SuperCDMS SNOLAB Dark Matter Experiment. https://doi.org/10.1063/1.5018995

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