We demonstrate the combination of fast-ion D-alpha spectroscopy (FIDA) and collective Thomson scattering (CTS) measurements to determine a common best estimate of the fastion velocity distribution function by velocity-space tomography. We further demonstrate a benchmark of FIDA tomography and CTS measurements without using a numerical simulation as common reference. Combined velocity-space tomographies from FIDA and CTS measurements confirm that sawtooth crashes reduce the fast-ion phase-space densities in the plasma center and affect ions with pitches close to one more strongly than those with pitches close to zero.
- Velocity-space tomography
- Collective Thomson scattering
- Fast-ion D-alpha spectroscopy
- Sawtooth crash
Jacobsen, A. S., Salewski, M., Geiger, B., Korsholm, S. B., Leipold, F., Nielsen, S. K., ... Weiland, M. (2016). Benchmark and combined velocity-space tomography of fast-ion D-alpha spectroscopy and collective Thomson scattering measurements. Plasma Physics and Controlled Fusion, 58(4), . https://doi.org/10.1088/0741-3335/58/4/042002