Determination of ion temperatures in magnetised plasmas by means of a rotating double probe
Electrical probes are widely used in magnetised plasmas such as the scrape-off layer of tokamaks to determine the electron temperature and density. A principal difficulty for the interpretation of probe signals in such plasmas is due to the fact that the flow of the particles to the probe pin is anisotropic and often turbulent. A well known approach aiming at a theoretical understanding of probe signals in magnetised plasmas is that known as `Bohm diffusion'. However, the effect of finite Larmor radii can also determine the electrical current as collected by a probe perpendicular to the magnetic field. Measurements are taken in the scrape-off layer of the tokamak TEXTOR where the conditions are such that the contribution of the diffusion to this current is insignificant, and the effect of finite ion Larmor radii prevails. It is then possible to determine the ion temperature by comparing the saturation currents, as measured by means of an electrical double probe, with the flux, as calculated by the Monte-Carlo method.
Bibliographic Reference: Paper presented: 16th European Conference on Controlled Fusion and Plasma Physics, Venezia (IT), March 13-17, 1989
Availability: Available from (1) as Paper EN 34790 ORA
Record Number: 198910634 / Last updated on: 1994-12-01
Original language: en
Available languages: en