ERROR ANALYSIS OF RIJNHUIZEN TOKAMAK PROJECT THOMSON SCATTERING DATA

At the Rijnhuizen tokamak project a double pulse multiposition Thomson scattering diagnostic has been operational since 1996. It has been installed for the study of small scale structures in electron temperature (Te) and density (ne). This diagnostic measures Te and ne with high spatial resolution (3 mm full width at half maximum, i.e., 2% of the minor radius) and high accuracy (3%–4% of Te and 2%–3% of ne in the range of 50 eV–6 keV and ne=5×1019 m−3.) In this article an extensive error analysis is performed on both statistical and systematic deviations. It is found that the instrument function of the detection branch has a smoothing effect on the noise. This reduces the statistical error on the Te and ne measurements on each spatial position, because the resolution of the instrument is oversampled. The long tail of the instrument profile of the entire diagnostic has a significant effect on the systematic deviations in the Te and ne determination. However, it does not affect the relative size of the smal...