GAMPIX: a new gamma imaging system for radiological safety and homeland security purposes

Localization of radioactive sources is a major issue for many applications in the nuclear industry. Gamma imaging is a powerful non-destructive technique, enabling to locate radioactive hot spots contained in a given area and well-adapted to this topic. Industrial gamma cameras have been commercialized by various companies for several years but present some limitations in terms of sensitivity, weight and ease of use in comparison with the requirements of end-users. For several years, CEA LIST has been developing a new generation of gamma camera, called GAMPIX. This system combines the Timepix pixellated chip, hybridized to a 1 mm CdTe substrate, a coded mask and a USB module dedicated to the interface between the gamma camera and a standard PC. It offers a technological breakthrough in comparison with the existing industrial gamma cameras. In this article, we present recent developments and experimental results obtained during in-situ measurements with the GAMPIX system. The latter are related to several application fields which can be addressed by this new gamma imaging system (decommissioning operations, radiological safety of operators in Nuclear Power Plant, Homeland Security purposes). (authors)