Geochemistry of Anthropocene: Novel application field of AMS

MALT (Micro Analysis Laboratory, Tandem accelerator), The University of Tokyo, is an ion beam analysis facility equipped with a 5MV tandem accelerator, a Cs-sputter negative ion source, mass analysis system, multi-Faraday cups for the stable isotope measurements, and final detectors designed for each bam analysis techniques. Among various beam analysis methods including NRA (Nuclear Reaction Analysis), ERDA (Elastic Recoil Detection Analysis), and PIXE (Particle Induced X-ray Emission), AMS (Accelerator Mass Spectrometry) is the most promising at MALT. Actually 70% of whole machine time is used for AMS. Since the completion of MALT facility in 1993, AMS for various nuclides had been developed, ¹⁰Be, ²⁶Al, ³⁶Cl, ⁴¹Ca, ¹²⁹I, and ²³⁶U as well as ¹⁴C. MALT is a pioneer of non-radiocarbon AMS in Japan. In Japan, there are 14 running accelerators for AMS, of which 8 accelerators are dedicated for ¹⁴C.