A computer-controlled particle collection and surface analysis system for tokamak scrape-of-layer analysis

A microcomputer controlled collection probe system has been designed and is currently in use at the TEXTOR tokamak in Jülich. The system enables a time and space resolved determination of the particle flux in five directions in the limiter shadow of the tokamak. Several series of measurements have been performed during the test of different limiter and heating experiments at TEXTOR, as well as for the evaluation of a wall cleaning program. A completing system for the surface analysis of the probes has been constructed at the Research Institute of Physics, Stockholm. By means of a 2 MeV Van de Graaff accelerator, Rutherford back scattering, nuclear reaction analysis and proton induced X-ray emission analysis of the probe surface is possible. With the help of a computer, programmed for automatic target scanning, data acquisition and storage, remote controlled analyses of exposed probes can now be done routinely with this new system. Recently, this analysis station has also been employed for samples exposed in the JET tokamak at Culham.