Advanced gamma ray transport by Monte Carlo simulation

In this chapter, gamma ray tracking by Monte Carlo simulation is investigated. Gamma transport is a complex problem, especially if the attenuating medium has an arbitrary structure, where analytical methods become inefficient. Monte Carlo methods using MCNP5 are applied to track gamma photons in different geometries. The basics of MCNP5 modeling are presented, where the reader learns the basic input cards relevant to gamma ray and how to implement them in MCNP5. Special techniques on using MCNP5 tallies are described, which are useful to study gamma transport. These techniques are demonstrated in three different applications where gamma attenuation, gamma dose, and gamma buildup factor are estimated using MCNP5 models created in this chapter. The results of MCNP5 are validated against the analytical solution, real data, as well as the G-P fitting formula. The good agreement observed between MCNP5 and other methods and data demonstrates the effectiveness of using Monte Carlo simulation in performing advanced analysis of gamma rays.