A Monte Carlo approach to food density corrections in gamma spectroscopy

Evaluation of food products by gamma spectroscopy requires a correction for food density for many counting geometries and isotopes. An inexpensive method to develop these corrections has been developed by creating a detailed model of the HPGe crystal and counting geometry for the Monte Carlo transport code MCNP. The Monte Carlo code was then used to generate a series of efficiency curves for a wide range of sample densities. The method was validated by comparing the MCNP generated efficiency curves against those obtained from measurements of NIST traceable standards, and spiked food samples across a range of food densities. (author)