Improved and automated krypton assay for low-background xenon detectors with Auto-RGMS

• Published in: The European physical journal. C, Particles and fields Vol. 85; no. 5; pp. 576 - 10
• Main Authors: Guida, Matteo, Lin, Ying-Ting, Simgen, Hardy
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.05.2025; Springer Nature B.V; SpringerOpen
• Subjects: Adsorbents; Astronomy; Astrophysics and Cosmology; Automation; Chromatography; Dark matter; Detectors; Elementary Particles; Gas detectors; Hadrons; Heavy Ions; Helium; Isotopes; Krypton; Measurement Science and Instrumentation; Neutrinos; Nuclear Energy; Nuclear Physics; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Rare gases; Regular Article - Experimental Physics; Robust control; Separation; String Theory; Xenon
• ISSN: 1434-6052; 1434-6044; 1434-6052
• DOI: 10.1140/epjc/s10052-025-14262-2

Ultra-sensitive quantification of trace radioactive krypton-85 ( 85 Kr) is essential for low-background experiments, particularly for next-generation searches of galactic dark matter and neutrino physics using xenon-based time projection chambers (TPCs). While the rare gas mass spectrometer (RGMS) represents the current state-of-the-art for krypton detection in the field, we are developing a fully automated system (Auto-RGMS) to overcome the limitations of its manual operation. Auto-RGMS incorporates a robust control system for rapid measurements and minimized systematic uncertainties. A primary goal is to reach detection limits in the low parts-per-quadrillion (ppq) range for natural krypton by improving the chromatography stage to enhance the separation of krypton from xenon. Investigations into various adsorbent materials identified two candidates. HayeSep Q offers a 12-fold improvement in chromatographic resolution for xenon/krypton separation compared to the previously used adsorbent. Alternatively, HayeSep D provides a more limited improvement in resolution while allowing a higher measurement frequency because of its moderate retention-induced contamination after each measurement. By automating krypton assays and achieving ppq sensitivity, Auto-RGMS will be an indispensable tool for next-generation detectors, maximizing their scientific potential.