| 摘要 |
Apparatus for non-invasively inspecting an object, such as an item of luggage, for explosives material comprises a multi-channel thermal neutron inspection system having a plurality of neutron irradiation chambers. Simultaneous operation of several channels increases maximum system throughput several times. Each chamber has a lithium neutron source, 56, (72 Fig. 2 not shown) which is stimulated to neutron production by a proton beam. Beam switching magnets (60 Fig. 2 not shown) are energised by pulsing to divert a common proton beam to each source in turn. The initial beam is generated by a radio frequency quadrupole accelerator 66. The advantages of this system are very low residual source activity and controllable neutron production thereby minimising safety hazards. The irradiation chamber may contain several different gamma ray detectors (80, 82, 84, 86 Figs. 2 and 3 not shown) to identify the elements present in explosives material. In addition a neutron radiography imaging means (88 Fig. 2 not shown) may be employed to identify the presence of potential shielding materials. <IMAGE> |
