Investigations on neutron-induced prompt gamma ray analysis of bulk samples

A systematic investigation was carried out for the improvement of the promp t gamma interrogation method used for contraband detection by the pulsed fa st/thermal neutron analysis (PFTNA) technique. Optimizations of source-dete ctor shielding and geometry, role of the type and dimension of the gamma de tector, attenuation of neutrons and gamma rays in bulky samples were also s tudied. Results obtained for both the shielding materials and elemental con tent of cocaine simulants have been compared with the values calculated by the MCNP-4A code. (C) 2001 Elsevier Science Ltd. All rights reserved.