Determination of D2O by photoneutron activation techniques

The possibility of using an intense 24Na gamma ray source for detection and determination of heavy water in samples has been investigated. The sample is irradiated, and the photoneutrons are detected by a set of six paraffin-shielded BF3 counters surrounding it. It is concluded that the presence of heavy water can be determined and its quantity measured. The photon source and water samples were in the form of coaxial cylinders, so that measurements were carried out with the same close geometry for highest accuracy. This system shows a detection sensitivity of D2O to be less than 0.1 mg. The equipment can also be used as a standard photoneutron source.