[19a-223-1~6] Advances and future prospects of accelerator mass spectrometry

[19a-223-2] Development of the Ultrasensitive Detection Method for Hard-to-measure Nuclides by means of Accelerator Mass Spectrometry

〇Kimikazu Sasa¹ (1.Univ. Tsukuba)

Keywords:Accelerator Mass Spectrometry (AMS), Femto-level isotope analysis, 6 MV tandem accelerator

The 6 MV Accelerator mass spectrometry (AMS) system for multi-nuclide measurements has been successfully established and operated at the University of Tsukuba since 2016. Long-lived radionuclides of ¹⁰Be, ¹⁴C (graphite and CO₂), ²⁶Al, ³⁶Cl, ⁴¹Ca and ¹²⁹I have been detected with a five-anode dE - E gas ionization detector in the range of ultra-low isotope ratios from 10^-10 to 10^-15. The AMS performance is entirely satisfactory to measure cosmogenic and anthropogenic nuclides for applications in the earth environmental research field by means of the 6 MV AMS system. Especially, a background of ⁴¹Ca AMS is reached to ⁴¹Ca/Ca ~ 3 × 10^-15 as the result of improved isobaric separation techniques. In addition, ⁹⁰Sr-AMS is currently under development. In this presentation, I will report the most advanced AMS facility and detection techniques for femto-level isotope analysis.