| 摘要 |
PURPOSE: To detect the presence of explosive in a traveling bag with sensitivity of high level by giving substantially uniform detecting response in a source or detector direction in an article. CONSTITUTION: Analyzing means 21 detects a pulse from a detector 15, and searches the pulse of a suitable range including 10.8MeV gamma ray corresponding to the synergistic action of the nucleus of nitrogen. A source is first positioned at a position 10, and a traveling bag 18 is placed symmetrically to an operating surface 17. The source is then moved to the forward position 14. At this position, the source is disposed on the axis of the virtual right circular cone of a space, its vertex is disposed in the bag 18, and the detector 15 is disposed on the circumference of the base of the cone. Further, the opposed pair of detector 15 is disposed on the virtual straight line crossed with the axis, and its intersection is the point that the source is disposed at the position 14. The output of the detector 14 is examined by the means 21. |
