[M-IS14] Paleoclimatology and paleoceanography

[MIS14-31] PIMS and SSAMS at Atmosphere and Ocean Research Institute, The University of Tokyo to study climate, environment and biological sciences

*Yusuke Yokoyama^1,2,3,4, Yosuke Miyairi¹, Takahiro AZE¹, Yohei Matsui⁴, Shoko Hirabayashi¹ (1.Atmosphere and Ocean Research Institute, University of Tokyo, 2.Department of Earth and Planetary Science, University of Tokyo, 3.Research School of Physics, The Australian National University, 4.Japan Agency for Marine-Earth Sciences)

Keywords:Accelerator Mass Spectrometry, PIMS, 14C

Although their abundances are very rare, cosmogenic nuclides produced in the atmosphere and their ratio to a terrestrial counterpart can provide detailed pictures of climate, carbon cycle, geomorphology, etc., and have therefore been widely used since their measurement became possible through Accelerator Mass Spectrometry (AMS). In particular, radiocarbon (¹⁴C) has been used to understand for climate and geochronological sciences (Larsen et al., 2017; Yokoyama et al., 2025a). Smaller AMS machines have been developed for the past two decades, and a single-stage accelerator mass spectrometry (National Electrostatic Corporation; NEC, SSAMS (YS-AMS)) was one of these machines, which was installed at the Atmosphere and Ocean Research Institute (AORI), University of Tokyo, and has been operating smoothly since 2013 (Yokoyama et al., 2019; 2022). The completely new concept of AMS was developed at NEC, called Positive Ion Mass Spectrometry (PIMS), and was just installed at AORI in Mach 2025 for the first-time outside Europe (Yokoyama et al., 2025b). Two AMS systems enhance the capability to conduct wide range of sciences using small scale radiocarbon measurements. In this presentation, we would like to introduce the present status of YS-AMS results including pollen-based radiocarbon dating and PIMS performance.

References:
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Yokoyama Y. et al., 2019 Nucl. Instr. Methods B, v455, 311-316.
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Yokoyama Y. et al., 2025b Nucl. Instr. Methods B, in press
Yokoyama Y. and Sproson A. 2025 Annual Reviews of Marine Science, in press