Determination of Multiple Compton Scattering Fractions in Gamma Densitometry by Monte Carlo Simulation

A method, based on Monte Carlo simulations, is given with the purpose of studying physical aspects on a Compton scattering densitometer. The energy spectrum of the scattered photons was determined by PENELOPE 2008 code to validate the physical model. A method to determine the single and multiple Compton scattering fractions is included to highlight physical aspects useful for response interpretation in cases where the main aim is to find zones with reduced continuity. By Monte Carlo simulations, we reproduced and improved empirical results related to the bulk density determination. Results related to the size of the volume explored in a semi-infinite concrete volume are given. Important advancement in densitometry applications were achieved in identifying nonhomogeneous zones by analyzing the scattered photons spectrum shape.