Polyethylene and copper samples were exposed underground 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 Pb-210 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.
Revised: March 18, 2020 |
Published: February 1, 2018
Citation
Stein M., D.A. Bauer, R.A. Bunker, R. Calkins, J. Cooley, B.M. Loer, and S. Scorza. 2018.Radon Daughter Plate-out Measurements at SNOLAB for Polyethylene and Copper.Nuclear Instruments and Methods in Physics Research. Section A, Accelerators, Spectrometers, Detectors and Associated Equipment 880.PNNL-SA-129611.doi:10.1016/j.nima.2017.10.054