Material Recognition by Using ²⁵²Cf Source

Non-destructive assay of parcels using a tagged ²⁵²Cf source and time of flight technique was studied. The method of material recognition was achieved by measuring simultaneously the transmission of neutron and gamma ray to determine the average atomic number. The automatic tomography was realized with the movement of motors and autostart of the digital acquisition system. With the calibration of the detectors, the average atomic number for each pixel of the sample was determined which allows one to recognize material with this method.