Accelerator Mass Spectrometry Analysis of 237NP in Environmental Samples

To determine the Np-237 concentration originating from global fallout in the environment, samples were collected from Guangxi, south of China, and measured by accelerator mass spectrometry (AMS) at CIRCE. Serials standard samples and environment samples were prepared and measured using Pu-242 as a tracer. The result indicates that the detection limit of Np-237 as low as 10(-15) g can be obtained. The concentration of (237) Np in the environmental samples is less than 49.09 pg/kg (i.e. 1.280 mBq/kg), and the most probable value of Np-237 is approximately 20 pg/kg (i.e. 0.53 mBq/kg)