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arXiv · 2411.05256

Radiopurity measurements of liquid scintillator for the COSINE-100 Upgrade

J. Kim·C. Ha·S. H. Kim·W. K. Kim·Y. D. Kim·Y. J. Ko·E. K. Lee·H. Lee·H. S. Lee·I. S. Lee·J. Lee·S. H. Lee·S. M. Lee·Y. J. Lee·G. H. Yu
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Abstract

A new 2,400 L liquid scintillator has been produced for the COSINE-100 Upgrade, which is under construction at Yemilab for the next COSINE dark matter experiment phase. The linear-alkyl-benzene-based scintillator is designed to serve as a veto for NaI(Tl) crystal targets and a separate platform for rare event searches. We measured using a sample consisting of a custom-made 445 mL cylindrical Teflon container equipped with two 3-inch photomultiplier tubes. Analyses show activity levels of $0.091 \pm 0.042$ mBq/kg for $^{238}$U and $0.012 \pm 0.007$ mBq/kg for $^{232}$Th.

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J. Kim, C. Ha, S. H. Kim, W. K. Kim, Y. D. Kim, Y. J. Ko, E. K. Lee, H. Lee, H. S. Lee, I. S. Lee, J. Lee, S. H. Lee, S. M. Lee, Y. J. Lee, G. H. Yu. 2024-11-08. Radiopurity measurements of liquid scintillator for the COSINE-100 Upgrade. https://doi.org/10.1088/1748-0221%2F20%2F06%2Ft06006

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