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arXiv · 2405.04901

Development of a method to measure trace level of uranium and thorium in scintillation films

K. Ichimura·K. Chiba·Y. Gando·H. Ikeda·Y. Kishimoto·M. Kurasawa·K. Nemoto·A. Sakaguchi·Y. Takaku·Y. Sakakieda
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Abstract

We have established a method to measure picograms-per-gram (pg g$^{-1}$) levels of $^{238}$U and $^{232}$Th in scintillation films by combining the dry ashing method and inductively coupled plasma mass spectrometry. Trace amounts of $^{238}$U and $^{232}$Th were measured in up to 2~g of the scintillation film with almost 100% collection efficiency. This paper details the experimental procedure, including the pretreatment of the samples and labware, detection limit of the method, collection efficiencies of $^{238}$U and $^{232}$Th, and measurement of $^{238}$U and $^{232}$Th in a polyethylene naphthalate film. This method is also applicable to $^{238}$U and $^{232}$Th measurements in other low-background organic materials for rare event search experiments.

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K. Ichimura, K. Chiba, Y. Gando, H. Ikeda, Y. Kishimoto, M. Kurasawa, K. Nemoto, A. Sakaguchi, Y. Takaku, Y. Sakakieda. 2024-05-08. Development of a method to measure trace level of uranium and thorium in scintillation films. https://doi.org/10.1093/ptep%2Fptae071

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