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Journal of the Korean Physical Society, Vol. 54, No. 2, February 2009, pp. 580$585

Design Study of a Compact Cyclotron for Accelerator Mass Spectrometry
tongE‡on Kim£
Research Institute and Hospital, National Cancer Center, Kyonggi 410-769

ghongEgheoul Yun —nd winE‰oung Youn
National Center for Inter-University Facilities, Seoul National University, Seoul 135-703

ƒonjong Wang
Centerfor Fusion Engineering, Korea Atomic Energy Research Institute, Daejeon 305-353

(Received 16 September 2008) An accelerator mass spectrometer (AMS) utilizing a small cyclotron has been designed. The system has a mass resolving power of over 4000, which is sucient to analyze a few AMS radioisotopes, including 14 C, for tracing or chronometric dating. The cyclotron can provide a high resolvingpower with a large number of turns and a high harmonic operation of the rf system and has the advantage of using both negative and positive ions in the analysis. A high transmission eciency is, in fact, a major goal in the design to compete with a Tandem AMS. A compact magnet with high stability, a sawtooth harmonic buncher and
at-topping rf system are the components adopted to achieve the goal.Also, large turn separations at injection and extraction are required, which can be done with adequate uses of the rst harmonic component of the main magnetic eld. The design of the cyclotron and injection beam line for the AMS has been studied.

PACS numbers: 29.20.Hm, 07.75.+h Keywords: Cyclotron, Accelerator mass spectrometer, Negative ion, Transmission eciency

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