Book Description

The DRF is the pulse height distribution for an incident radiation, and is also a PDF which has the properties of always being greater than or equal to zero and also integrates to unity. The application of the DRF on a simulated spectrum results in the benchmarking of the simulation results with experimental results. The results are the nice Gaussian shapes that are caused by the statistical fluctuations in the energy and collection efficiency of the detector. To find the perfect simulation of the DRF is impossible due to the fact that the detector might have imperfections, where electrons can essentially become trapped and not be collected. One must rely on empirical models of nonlinearity and simulation data to do this. This is what CEARÃØâ'Ơâ"Øs DRF code g03 does. The time consuming task of a code like g03 is the time it takes to simulate the Monte Carlo simulation, in particular the electron transport of it. G03 couples rigorous gamma ray transport with very simple electron transport. By this methodology the non-linearity and the variable flat continua part of the DRF is accounted for. There are some problems and upgrades that needed to be addressed, for instance the difference in the valley region between the Photopeak and Compton Edge and parts of the Compton Continuum. This Monte Carlo simulation also simulates the detector as a bare crystal. It was found that this could account for as much of a reduction of as much 5 percent of the incident energy. And also distort the response function in the lower energy range of the function. For this MCNP was employed to simulate the difference between the bare and covered crystal. The MCNP simulation also included a surface current tally for electrons and photons on the interface between the can and the crystal, and also the interface between the side of the crystal and the can. From the results of the simulation of the can and no can simulation for the pulse height spectra are different. It here when it was determined.