Evaluation of key detector parameters for isotope identification

The algorithm used for isotope identification onboard a radioisotope identifier (RIID) plays a key role in obtaining a correct identification. The majority of RIIDs deployed by the United States Department of Homeland Security are based on NaI spectrometers. Their performance in isotope identification has been well-documented. It has been demonstrated that the secondary analysis of spectra by a trained spectroscopist is frequently necessary to resolve problems in the RIIDs identification. It is also clear that trained spectroscopists are capable of identifying complicated, multiple-line sources with even the poorest resolution detectors such as Nal. This paper seeks to understand the factors in detector performance such as energy resolution that play an important role in isotope identification.