世界核地质科学2025，Vol.42Issue(2)：423-435,13.
用于热电离质谱仪的Daly检测器铀同位素分析性能验证
Performance validation of a Daly detector for thermal ionization mass spectrometry
摘要
Abstract
To meet the requirements of thermoionization mass spectrometry(TIMS)for the determination of low-abundance isotopes,it is necessary to configure a secondary electron multiplier(SEM)or Daly detector ion counting detector on the TIMS.Compared to SEM,Daly offers high gain,low noise,good linearity,long service life,and the photomultiplier tube is located outside the instrument's vacuum system and easy to replace,making it more cost-effective.The authors developed Daly detector consists of a detection chamber,an ion conversion pole,a plastic scintillator,a fast-response photomultiplier tube,a preamplifier,a single-photon counter,a power supply,and the measurement and control software.The response gating of the Daly detector can be adjusted between 0.1～2 V,the photomultiplier tube has a high voltage of 800～900 V,the ion counting background is less than 0.1 cps,and the highest count rate is 40 Mcps.In this paper,the performance of the Daly detector was verified by uranium isotope composition determination,and the results showed that the intra-test precision of Daly for the CRM0002 isotope abundance of 235U/238U was 0.073%,and the intra-test precision of the isotope abundance of UTB500 was 0.139%,0.056%and 0.214%respectively for 234U/238U,235U/238U and 236U/238U,which met the requirements of ASTM C1625-19.关键词
热电离质谱仪/Daly检测器/前置放大器/FPGAKey words
thermal ionization mass spectrometer/Daly detector/preamplifier/FPGA分类
天文与地球科学引用本文复制引用
乔麓伊,王若鸣,李黎,董守智,吴磊,戴光钏,李梦清,郭冬发,李伯平,刘桂方,向波,韦梓渝,汤书婷,谭靖,张泽..用于热电离质谱仪的Daly检测器铀同位素分析性能验证[J].世界核地质科学,2025,42(2):423-435,13.基金项目
核技术研发项目(编号:测H2402)资助 Supported by Nuclear Technology Research and Development Projects(No.测H2402),China Atomic Energy Authority （编号:测H2402）
