Investigation of the consistency of magnetic and soft X-ray plasma position measurements on TCV by means of a rapid tomographic inversion algorithm
A streamlined algorithm for tomographic inversion is presented that allows rapid post-discharge reconstruction of the soft X-ray emissivity evolution in the TCV tokamak. Simultaneously it determines the centre of gravity of the emissivity that may serve as a reliable measurement of the plasma position that is independent of magnetic measurements. Tests of the algorithm were performed using shaped phantom datasets and all past SXR measurements were processed to obtain plasma position statistics. Multiple linear regression is applied in matching the results with the magnetic axis data. Systematic functionalities including magnetic field dependence and drift of the magnetic axis are observed. The joint resolution limit of magnetic and SXR position measurements at TCV is derived from the residual discrepancies and equals 2.2mm and 3.1mm in the radial and vertical directions, respectively.
Bibliographic Reference: EPFL internal report LRP 732/02, October 2002. pp.29.
Availability: Available free of charge from: École Polytechnique Fédérale de Lausanne (EPFL), Ecublens, CH-1015 Lausanne Fax +41-21-6934747
Record Number: 200215494 / Last updated on: 2002-11-07
Original language: en
Available languages: en