RADIATION TRANSPORT SIMULATION STUDIES USING MCNP FOR A COW PHANTOM TO DETERMINE AN OPTIMAL DETECTOR CONFIGURATION FOR A NEW LIVESTOCK PORTAL A Thesis

Radiation Transport Simulation Studies Using MCNP for a Cow Phantom to Determine an Optimal Detector Configuration for a New Livestock Portal. (August 2012) Joe Justina, M.Sc., Mangalore University Co-Chairs of Advisory Committee: Dr. Craig M. Marianno Dr. Sunil S. Chirayath A large radiological accident will result in the contamination of surrounding people, animal, vegetation etc. In such a situation assessing of the level of contamination becomes necessary to plan for the decontamination. There are plans existing for evaluating contamination on people. However, there are limited to no plans to evaluate animals. It is the responsibility of the United States Department of Agriculture (USDA) to decontaminate animals. So the objective of this thesis work was to design a scalable gamma radiation portal monitor (RPM) which can be used to assess the level of contamination on large animals like cattle. This work employed a Monte Carlo NParticle (MCNP) radiation transport code for the purpose. A virtual system of cow, radiation source representing the contamination, cattle chute and different detector configurations were modeled. NaI scintillation detectors were modeled for this work. To find the optimal detector size and configuration, different detector orientations were simulated for different source positions using the MCNP code. Also simulations were