Highly efficient on-site detection of neutron sources with the INT measurement car DeGeN

Counter-acting the potential misuse of nuclear and radioactive material has been a subject of tremendous importance for quite a while, and the detection of such material is a key figure to counter-acting measures in that respect. Especially regarding nuclear material, detecting gamma and neutron radiation simultaneously on-site with high efficiency provides a good chance of retrieving such material during transport after it was removed from nuclear facilities, either as a malicious act or simply by chance. The Fraunhofer INT's (Institute for Technological Trend Analysis) measurement car DeGeN (detection of gammas including neutrons) is equipped with highly sensitive 3He neutron detectors and 12 l plastic detectors for gammas. After a reconfiguration of the measurement system, including new gamma detectors, the INT was given the opportunity of verifying the system's detection limits at the premises of WIS (Bundeswehr Research Institute for Protective Technologies and CBRN Protection) in Munster, Germany. Two different neutron sources were used for the experimental determination of the detection limits concerning neutrons. The results were then compared to theoretical detection limits which had been calculated previously. The results proved to be in good agreement overall.