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arXiv · 1708.09476

Radon Daughter Plate-out Measurements at SNOLAB for Polyethylene and Copper

Matthew Stein·Dan Bauer·Ray Bunker·Rob Calkins·Jodi Cooley·Ben Loer·Silvia Scorza
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Abstract

Polyethylene and copper samples were exposed to the underground air at SNOLAB for approximately three months while several environmental factors were monitored. Predictions of the radon-daughter plate-out rate are compared to the resulting surface activities, obtained from high-sensitivity measurements of alpha emissivity using the XIA UltraLo-1800 spectrometer at SMU. From these measurements, we determine an average $^{210}$Pb plate-out rate of 249 and 423 atoms/day/cm$^{2}$ for polyethylene and copper, respectively, when exposed to radon activity of 135 Bq/m$^{3}$ at SNOLAB. A time-dependent model of alpha activity is discussed for these materials placed in similar environmental conditions.

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Matthew Stein, Dan Bauer, Ray Bunker, Rob Calkins, Jodi Cooley, Ben Loer, Silvia Scorza. 2017-08-30. Radon Daughter Plate-out Measurements at SNOLAB for Polyethylene and Copper. https://doi.org/10.1016/j.nima.2017.10.054

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