Doru Pacesila, Iuliana Stanciu, Razvan Gornea, William E. Kieser, Nimal De Silva, Albert Zondervan, Barbara Francisco, Michaela Froehlich, Michael Hotchkis, Marie-Cécile Piro and Guillaume Giroux
{"title":"Assay of lead-210 in metallic copper via accelerator mass spectrometry","authors":"Doru Pacesila, Iuliana Stanciu, Razvan Gornea, William E. Kieser, Nimal De Silva, Albert Zondervan, Barbara Francisco, Michaela Froehlich, Michael Hotchkis, Marie-Cécile Piro and Guillaume Giroux","doi":"10.1039/D5JA00105F","DOIUrl":null,"url":null,"abstract":"<p >This study focuses on the precise quantification of <small><sup>210</sup></small>Pb contamination in metallic copper, an essential construction material of ultra-sensitive detectors in astroparticle physics, by Accelerator Mass Spectrometry. For the most stable and durable anion beam current from the Cs sputter source, PbF<small><sub>2</sub></small> in a mixture with fine Ag powder was found to be preferable over PbO + Ag. After tandem acceleration and electron stripping with helium, the maximum <small><sup>206</sup></small>Pb<small><sup>3+</sup></small> current was 0.11 μA, and the <small><sup>210</sup></small>Pb detection efficiency was 1.3 × 10<small><sup>−4</sup></small>. Investigation of several methods to extract lead from copper, with HNO<small><sub>3</sub></small>, NH<small><sub>4</sub></small>OH, and H<small><sub>2</sub></small>SO<small><sub>4</sub></small>, led to chemical recovery rates up to 92%. Following the development of chemical and target preparation procedures, an upper limit of <small><sup>210</sup></small>Pb = 62 mBq kg<small><sup>−1</sup></small> was determined for the NEWS-G copper (Aurubis) sample, consistent with previous results obtained by α-spectrometry. Tests with copper plates exposed to an atmosphere of <small><sup>222</sup></small>Rn (1625 Bq m<small><sup>−3</sup></small>) for 182 hours showed significant <small><sup>210</sup></small>Pb surface contamination (0.56 ± 0.16 Bq m<small><sup>−2</sup></small>), underscoring the importance of minimizing radon in spaces where metallic copper is chemically and/or physically processed.</p>","PeriodicalId":81,"journal":{"name":"Journal of Analytical Atomic Spectrometry","volume":" 7","pages":" 1852-1861"},"PeriodicalIF":3.1000,"publicationDate":"2025-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Analytical Atomic Spectrometry","FirstCategoryId":"92","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2025/ja/d5ja00105f","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, ANALYTICAL","Score":null,"Total":0}
引用次数: 0
Abstract
This study focuses on the precise quantification of 210Pb contamination in metallic copper, an essential construction material of ultra-sensitive detectors in astroparticle physics, by Accelerator Mass Spectrometry. For the most stable and durable anion beam current from the Cs sputter source, PbF2 in a mixture with fine Ag powder was found to be preferable over PbO + Ag. After tandem acceleration and electron stripping with helium, the maximum 206Pb3+ current was 0.11 μA, and the 210Pb detection efficiency was 1.3 × 10−4. Investigation of several methods to extract lead from copper, with HNO3, NH4OH, and H2SO4, led to chemical recovery rates up to 92%. Following the development of chemical and target preparation procedures, an upper limit of 210Pb = 62 mBq kg−1 was determined for the NEWS-G copper (Aurubis) sample, consistent with previous results obtained by α-spectrometry. Tests with copper plates exposed to an atmosphere of 222Rn (1625 Bq m−3) for 182 hours showed significant 210Pb surface contamination (0.56 ± 0.16 Bq m−2), underscoring the importance of minimizing radon in spaces where metallic copper is chemically and/or physically processed.