Effects of ICRF waves on the axial transport of mirror confined ions in GAMMA 10/PDX
POSTER
Abstract
In the GAMMA 10/PDX tandem mirror, end-loss ions are used in the studies on divertor physics. Plasmas are produced with Ion Cyclotron Range of Frequency (ICRF) waves at the central cell, which has a simple mirror configuration. The peaked profiles near the loss-cone boundary in the pitch angle distribution of the end-loss ions are clearly observed. This implies the main source of the end-loss ions is the pitch angle diffusion due to ion-ion collisions in the mirror confined region. In order to control the temperature of the end-loss ions, additional ICRF waves are applied in the central cell and the other cells. When the ICRF waves, which have resonance layers in the central cell are applied, the end-loss ions with pitch angle near the 0 degree are increased. This will indicate that the ions are dropped into the loss-cone by the large pitch angle scattering due to wave-particle interactions. In addition, the interaction with Alfv\'{e}n-Ion-Cyclotron (AIC) waves, which are excited spontaneously due to strong anisotropy of ion temperature is observed.
*This work was partly supported by the bidirectional collaborative research program of the National Institute for Fusion Science, Japan (NIFS19KUGM141, NIFS17KUGM132 and NIFS19KUGM141) and JSPS KAKENHI Grant Number 18K03574.