Underwater detection of a TNT explosive

Tagged neutron inspection system was used for the detection of explosive in water. Neutrons were produced in d+t nuclear reaction with API 120 sealed tube neutron generator. Five kilograms of the TNT explosive were measured in a pool filled with water. Measurements were done in target in, target out configuration. In addition, a sandwich made of 6 mm thick iron plates with explosive in between was placed between two layers of sea sediments and measured underwater. Sediments were collected in the Adriatic Sea. Measurements were repeated with TNT explosive replaced by rocks of similar size and shape. Neutron tube was rotated in order to find the position and dimension of explosive (rocks) in the sandwich. It was found that TNT can be detected in the water. Morover, TNT and, sea rocks have had distinguished ratio of carbon and oxygen while measured between 6 mm thick iron plates and placed between layers of sediments.