Particle diagnostics

Three techniques for particle diagnostics of magnetically confined fusion plasmas are reviewed: charge exchange neutral particle analysis, Rutherford scattering, and heavy ion beam probes. The physical basis and instrumentation for each technique are described Typical examples obtained by these diagnostics are presented Charge exchange analysis is used for ion temperature measurements in small- and medium-sized plasma devices and for the study of the ion energy distribution function, especially in the suprathermal energy range. It also provides an ion isotope composition determination that is a high-priority task for ITER. Rutherford scattering enables local measurements of the ion temperature as well as measurements of the ion collective velocity. The heavy ion beam probe diagnostic gives a unique opportunity to measure locally the electric plasma potential and, by that, the electric field profile in a plasma and its influence on confinement. Other significant options of this diagnostic are the measurements of the local electron density and fluctuations in these quantities. Prospects for the application of the various techniques to ITER are discussed.