TELEVISION IMAGING-SYSTEM FOR FAST-NEUTRON RADIOGRAPHY USING BABY CYCLOTRON

A television imaging system for fast neutron radiography (FNR-TV) deve loped using the fast neutron source reactor YAYOI was applied to the b aby-cyclotron based fast neutron source to get images of thick objects quickly. In the system the same technique as a current television ima ging system of thermal neutron radiography was applied, while the lumi nescent converter was used to detect fast neutrons. Using the CR39 tra ck etch method it took about 7 h to get an image, while the FNR-TV onl y 20 s enough for taking the same object. However the FNR-TV imaging r esult of the simulation model of a large explosive device for the spac e launch vehicle of H-2 type was not so good as the image taken with t he CR39 track etch method. The reason was that the luminescence intens ity of the FNR-TV converter was a quarter of that in the YAYOI.