Fast neutron mapping through CR-39 films

The era of Solid state nuclear track detectors (SSNTDs) began in 1960 when charged particle tracks were revealed by chemical etching by the trio of Fleischer, Price and Walker of GEC Laboratory, U.S.A. Simplicity of this technique, insensitivity to gamma radiations and capability to store information without complex electronic circuits have lead to an intense interest for the development of number of these detectors for wide applications in the modern science. Keeping the special features in view CR-39 (Polyallyl diglycol carbonate) one of the SSNTD, is the most sensitive detector for neutron monitoring applications. CR-39 film is important for fast neutron mapping applications i.e. neutron dosimetry, spectrometry, personnel and area monitoring, shielding evaluation etc. This material has preferred over rival techniques because of low cost, high degree of reproducibility, insensitive to gamma radiation, easy to process and has capability to record recoil protons tracks. This detector has been used at Defence Laboratory, Jodhpur for fast neutron dosimetry, area monitoring and shielding evaluation of various materials. (author)