Experimental investigation of a low-cost solid state detector with high spatial resolution for ultracold neutrons

An ultracold-neutron detector based on a commercial CMOS webcam was investigated for the first time at the instrument PF2 of the Institut Laue-Langevin. In this feasibility study two different neutron converters, 10B and 6Li, were compared. For a standard high-definition videochip with an active area of 3.2 mm x 4.8 mm, a spatial resolution of ∼0.3 μm is possible to obtain. For a 430 nm thin 6Li converter, positioned in front of the webcam, a detection efficiency of (47.1± 0.6)% was found. (orig.)