Design of an ion temperature diagnostic based on neutral beam scattering

Small-angle neutral beam scattering will be used on the STOR-M tokamak to obtain space and time-resolved measurements of the ion temperature. Advantages of the technique and experimental considerations leading to the design are discussed. It is expected that a 20–30-keV helium beam of 35–65-A/m2 current density together with a large area chevron channel-plate detector and automatic data handling will allow direct determination of ion temperatures at an accuracy of 10%, a temporal resolution of 40 µs, and a spatial resolution better than 1 cm