Validation of the “kick model” of Alfvén eigenmode induced fast-ion transport via Orbit Tomography*

A new data analysis method, Orbit Tomography, that can reconstruct the entire fast-ion distribution from experimental measurements is used to validate models of beam-ion transport. In an ideal scenario increasing heating power should correlate with increased fusion performance. However, in the presence of many overlapping Alfvén eigenmodes (AEs) the fast-ion density profile becomes resistant to increased heating. This is caused by the AEs redistributing the fast ions, degrading confinement. The "kick model", which models the "kicks" the fast ions experience due to the AEs, has been shown to be effective at reproducing experimental results. However, direct comparison of the predicted fast-ion distribution with experiment has been out of reach until recently. With Orbit Tomography, the kick model's local phase-space predictions can be validated. In this work fast-ion phase-space effects predicted by the kick model will be compared with Orbit Tomography reconstructed fast-ion distributions form experiment.