Alpha particle loss diagnostics in TFTR and tokamak reactors

Measurement of alpha particle loss rates to the first wall is of importance in planning tokamak fusion reactors, since large loss rates can adversely affect performance. A set of scintillator-based probes has been operated in TFTR to measure alpha particle losses during its DT campaign. A sample exposure probe has also provided alpha particle loss data under some conditions. These technologies, along with infrared imaging and Faraday cups, may be adaptable to alpha particle loss measurements in ITER or other reactor-scale tokamaks. Constraints on detector operation in a reactor environment are discussed.