Monte Carlo simulation of response function for a NaI(Tl) detector for gamma rays from 241Am/Be source

The general purpose computer code MCNP4B was used to simulate the response function of a bare NaI(Tl) detector crystal for gamma rays from an 241Am/Be source capsule. The simulated spectral shape generated by the MCNP4B code was compared with the measured spectral shape obtained using a gamma-ray spectrometer with a cylindrical shape, 7.62 cm×7.62 cm, NaI(Tl). In general, the agreement between the simulation and the experimental response function was good.