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arXiv · 1910.02617

Development of Low Radioactive Molecular Sieves for Ultra-Low Background Particle Physics Experiment

H. Ogawa·K. Abe·M. Matsukura·H. Mimura
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Abstract

This study develops low radioactive molecular sieves (MS) for ultra-low background particle physics experiment. The manufactured MS is of type 4A. $^{226}$Ra and $^{232}$Th have concentrations of about 57 and 198 mBq/kg, respectively, measured by applying high-purity germanium (HPGe) measurement. The reduction of the radioactivity from the commercial one is about 99 and 97 percent for $^{226}$Ra and $^{232}$Th, respectively. Furthermore, the radon emanation rate from MS filter is about 2.1 mBq, which is measured by utilizing pin-photo type radon detector. This developed MS is expected to remove the impurity from the noble gas, in which low radioactivity is needed such as dark matter search experiment.

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H. Ogawa, K. Abe, M. Matsukura, H. Mimura. 2019-10-07. Development of Low Radioactive Molecular Sieves for Ultra-Low Background Particle Physics Experiment. https://doi.org/10.1088/1748-0221/15/01/p01039

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