Software-based Data Processing Methods for Uranium Isotope Measurements by a Self-developed Multi-collector Mass Spectrometry

Multi-collector thermal ionization mass spectrometry (TIMS) is widely used for high-precision uranium isotope ratio measurements in nuclear material analysis. In this work, a self-built TIMS system (TIMS-II) and its dedicated measurement software were developed with emphasis on software-oriented data processing and correction methods. Algorithms for peak center identification, software-controlled background evaluation, mass-dependent fractionation correction, and inter-Faraday cup efficiency correction were implemented and integrated into a unified measurement workflow. The performance of the developed system and software was evaluated through uranium isotope measurements using natural uranium and the CRM U500 standard solution. Repeated measurements demonstrate stable and reproducible results, and the corrected ²³⁵ U/ ²³⁸ U isotope ratios obtained for CRM U500 agree with the certified value within its stated uncertainty. The results indicate that the proposed software-based data processing framework provides a practical and reliable approach for uranium isotope analysis using self-built TIMS systems.