Locating, Identifying and Quantifying Radioactive Sources in an Inaccessible Area

In April 2007 an international In-Situ Intercomparison Scenario (TSTS2007) exercise was organized in cooperation between the Austrian Research Centers ARC and the IAEA and was conducted at Wiener Neustadt (Austria). A team from the Radiation Safety Division at Soreq Nuclear Research Center took part in the exercise. The exercise consisted of 10 tasks oriented to exercise identification and quantification of radioactive contamination due to reactor release, radiological terror or other accidents with radioactivity, which result in radiological debris, hidden sources, and unknown sources in containers, either shielded or unshielded cases. Several tasks were designed to test special skills, like the ability of the team to identify and quantify a buried source. In this work we present Task No. 2 called by the Organizers ''Localization - Drive by'' and estimated by them to be the most demanding task of the whole exerciseni. We also present the proposed solution of our team, which is based on the combination of signal intensities and geometrical properties of the source-detector configuration