Pulse shape discrimination with stilbene scintillators for a neutron camera

In a feasibility study the Physics Institute III B develops a neutron detector for a radiography system using fast neutrons, which can be used to improve probe analyses in extractive industries. The aim is to build a 4$/times$4 pixel camera prototype, consisting of 16 stilbene scintillator crystals, coupled to silicon photomultipliers. The main challenge is the discrimination between scintillation signals from neutrons and gamma-rays, which are produced by radioactive neutron sources as well as neutron generators. The separation of the signals is achieved by exploiting different pulse shapes, due to longer decay time components for neutron induced excitations in stilbene. This pulse shape discrimination technique is presented for individual stilbene crystals as well as the optimisation of important parameters.