{"paper":{"title":"Identification of $^{210}$Pb and $^{210}$Po in the bulk of copper samples with a low-background alpha particle counter","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"physics.ins-det","authors_text":"A. Takeda, B. D. Xu, B. S. Yang, G.Kanzaki, H. Ogawa, H. Sekiya, H. Takiya, K. B. Lee, K. Fushimi, K. Hiraide, K. Hosokawa, K. Ichimura, K. Kanzawa, K. Kobayashi, K. Martens, K. Masuda, K. Miuchi, K. Nishijima, K. Sato, M. K. Lee, M. Kobayashi, M. Miyasaka, M. Nakahata, M. Yamashita, N. Oka, N. Y. Kim, O. Takachio, R. Fujita, R. Kegasa, S. Moriyama, S. Nakamura, S. Tasaka, T. Norita, XMASS Collaboration: K. Abe, Y. D. Kim, Y. Fukuda, Y. H. Kim, Y. Itow, Y. Kishimoto, Y. Suzuki, Y. Takeuchi","submitted_at":"2017-07-20T08:27:21Z","abstract_excerpt":"We established a method to assay $^{210}$Pb and $^{210}$Po contaminations in the bulk of copper samples using a low-background alpha particle counter. The achieved sensitivity for the $^{210}$Pb and $^{210}$Po contaminations reaches a few mBq/kg. Due to this high sensitivity, the $^{210}$Pb and $^{210}$Po contaminations in oxygen free copper bulk were identified and measured for the first time. The $^{210}$Pb contaminations of our oxygen free copper samples were 17-40 mBq/kg. Based on our investigation of copper samples in each production step, the $^{210}$Pb in oxygen free copper was understo"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1707.06413","kind":"arxiv","version":2},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}