A single-stage accelerator mass spectrometer and its applications at Guangxi Normal University

Abstract

GXNU-AMS, a compact 14C accelerator mass spectrometer jointly developed by the Guangxi Normal University and China Institute of Atomic Energy, was installed and commissioned in Guangxi Normal University in 2017. It is the first original single-stage AMS facility and one of the lowest designed energy AMS systems in China. Without the traditional mode of a SF6 pressure tank, the terminal of the system was designed as an open insulated high-voltage platform, which reduces the accelerator size to ∼2.5 m × 4.5 m. Helium gas stripping was used for eliminating the interference of molecular ions, and the maximum operating voltage is ∼200 kV. During several years of operation, its performance has been continuously improved and it has been applied in multidisciplinary fields. Currently, the measurement accuracy of the instrument is ∼0.6 % and the measurement sensitivity is 14C/12C ∼ 3 × 10−15 (equivalent to a 14C age of approximately 47,000 years.), which can meet the measurement requirements in the fields of life sciences and archaeology. In this study, the performance characteristics and operation of GXNU-AMS are discussed and several application studies being conducted by the GXNU-AMS group are presented.