An Inter-laboratory comparison study on C measurements between two AMS laboratories of Nagoya University and JAEA Mutsu

Nakamura, Toshio*; Tanaka, Takayuki; Kabuto, Shoji; Ota, Tomoko*

An inter-laboratory comparison of C dating studies with AMS were performed between Nagoya University and JAEA. Two kinds of archeological samples used for the intercomparison were offered from the Education Board of Nirasaki city. One part of them was a charred rice sample with known historical age, which was collected from the ruin of Shimpu-Jo castle remains. The rice was charred when the castle was burnt in 1582, when the castle was abandoned by Katsuyori Takeda during the battle against the combined military forces of Oda and Tokugawa families. The other samples were charred pyrenes of peach and nutshells of Japanese walnut collected from the Shukujiri-Daini-Iseki archeological site. The results from the two AMS laboratories were quite consistent within statistical uncertainties. In addition, calibrated C ages for the charred rice samples were also consistent with the historical age when the Shimpu-Jo castle was burnt down.