Quantity   Component name
1 × Scintillator Crystal 2 Inch Thalium-doped Sodium Iodide Crystal
1 × Hamamatsu R3998-02 Photomultiplier Tube PMT made for High Energy Physics and Scintillation Counting
1 × High Voltage Power-Supply Jim Williams' design for a -1KV, low noise PSU
1 × Voltage divider for PMT Necessary to bias the dynodes to the required potential for the photoelectric magic to happen
1 × Housing for the detector Needs to be light-tight