Position-Sensitive Detectors for Shielding Tests of Spent Fuel Shipping Casks

A system for measuring spatial distributions of dose rates around the surface of shipping casks is described. A He-3 counter surrounded by a 30 mm thick moderator is used as a position-sensitive neutron detector based on the charge division method. A one-dimensional array of ten NaI(Tl) scintillation counters is used as a position-sensitive gamma-ray detector.