Ion trajectory simulations for the TEXT upgrade 2 MeV heavy ion beam probe (abstract)

Abstract

Ion trajectory calculations play a key role in the design of a heavy ion beam probe system and the interpretation of its measurements. In the case of the HIBP for TEXT Upgrade presently under construction, ion trajectory simulations showed that ions with energies up to 2 MeV have to be injected and detected at two different locations in order to make measurements over the whole plasma cross section. Trajectory calculations also provide essential guidelines for the construction of system components such as energy analyzers. In order to measure fluctuation-induced transport (ñ, φ̃, phase, k), the analyzers will have multiple slits. The distance of the apertures that gives reasonable distances of the sample volumes in the plasma was determined, and examples for sample volumes sizes and shapes, which determine the quality of the measurements, are presented. Another issue involving the quality and the understanding of HIBP measurements is ion beam attenuation. The trajectory code has been used to estimate the signal strength that can be expected from the 2 MeV HIBP. This work was supported by DOE.