Performance of the new iodine-129 beamline at JAERI-AMS

Suzuki, Takashi ; Aramaki, Takafumi; Kitamura, Toshikatsu; Togawa, Orihiko 

At the Japan Atomic Energy Research Institute, an Accelerator Mass Spectrometer which was installed in Mutsu establishment has two independent beam lines. We verified the precision, the accuracy and the detection limit at this AMS iodine line. Acceptance test for I measurement was carried out on two consecutive days and the I/I ratios obtained during these two days were (7.4970.119) 10 and (7.2090.050) 10 , respectively and the relative standard deviations from the I/I averages per sample were 1.6 % and 0.7 %, respectively. Seawater samples were collected in the western North Pacific and off Rokkasho, Japan before the operation of a nuclear fuel reprocessing plant. Seawater samples preparation for I -AMS measurement was performed by an extraction method. This paper was summarized the performance of this AMS iodine line and measurement results of I/I ratio in seawater samples.