Detection of concealed radioactive and nuclear materials in situ

The worldwide terrorist threat of using nuclear respectively radioactive material in conjunction with explosives is increasing significantly. For prevention of such an act systems and methods are essential for fast search of such material and, after detection, identification of the substance. For the search we have a car at our disposal, which is equipped with very sensitive gamma and neutron detectors. A gross first identification is possible also. Then precise non-destructive measurements are performed with portable detectors of high energy resolution and efficiency or by scanning of buildings or objects with a gamma camera. Nevertheless, in some cases no suspect material is detected with all these sensitive passive methods, even though a reasonable suspicion exists. Then active methods will be employed by pulsed irradiation of the suspect object with neutrons produced by a small neutron generator (neutron interrogation). With all these techniques it is possible to determine the presence of radioactive respectively fissionable materials in situ, as well as type and quantity within certain limits. Hence information will be gained on the possible risk potential and thus further measures will be recommended taking radiological aspects into account. All these systems and procedures are provided by our institute for support of security authorities.