Combination of fast-ion diagnostics in velocity-space tomographies

TitleCombination of fast-ion diagnostics in velocity-space tomographies
Publication TypeJournal Article
Year of Publication2013
AuthorsM. Salewski, B. Geiger, S.K. Nielsen, H. Bindslev, M. García-Muñoz, W.W Heidbrink, S.B Korsholm, F. Leipold, J. Madsen, F. Meo, P.K Michelsen, D. Moseev, M. Stejner, G. Tardini, ASDEX Upgrade Team
JournalNuclear Fusion
Volume53
Number6
Pagination063019
Abstract

Fast-ion D α (FIDA) and collective Thomson scattering (CTS) diagnostics provide indirect measurements of fast-ion velocity distribution functions in magnetically confined plasmas. Here we present the first prescription for velocity-space tomographic inversion of CTS and FIDA measurements that can use CTS and FIDA measurements together and that takes uncertainties in such measurements into account. Our prescription is general and could be applied to other diagnostics. We demonstrate tomographic reconstructions of an ASDEX Upgrade beam ion velocity distribution function. First, we compute synthetic measurements from two CTS views and two FIDA views using a TRANSP/NUBEAM simulation, and then we compute joint tomographic inversions in velocity-space from these. The overall shape of the 2D velocity distribution function and the location of the maxima at full and half beam injection energy are well reproduced in velocity-space tomographic inversions, if the noise level in the measurements is below 10%. Our results suggest that 2D fast-ion velocity distribution functions can be directly inferred from fast-ion measurements and their uncertainties, even if the measurements are taken with different diagnostic methods.

URLhttp://stacks.iop.org/0029-5515/53/i=6/a=063019
DOI10.1088/0029-5515/53/6/063019
Division

FP

Department

PDG

PID

23553dfb974e7824d2430fb92cca1052

Alternate TitleNucl. Fusion

Go back one page.