Determination of 134Cs activity with the sum-peak method using a well-type germanium detector

The new sum peak method was applied to the samples containing both 137Cs and 134Cs using a well-type HPGe detector. The standard sources containing 137Cs and/or 134Cs were measured via a well-type HPGe detector. The activities estimated by the new sum-peak method agreed with the certified activities of the standard sources. It was proved that the activities of the samples collected around Fukushima Daiichi Nuclear Power Plant can be estimated by the new sum-peak method.