Calibration of scintillation detectors for MeV charged fusion products

The light output of ZnS scintillators used to detect escaping fusion products in the TFTR Tokamak is studied with 3.5-MeV alpha and 3-MeV proton beams. The emitted light first increases linearly with beam current and then saturates. In all cases investigated, the saturations start at a fairly constant absorbed power density of about 1 mW/cm2. The scintillators have adequate time response up to 50–100 kHz.