Neutral Transport Analysis in Non-axisymmetric Anchor Region of the GAMMA 10 Tandem Mirror Using a Monte-Carlo Simulation

Transport of neutral particles in non-axisymmetric anchor region of the GAMMA 10 tandem mirror is described in terms of a Monte-Carlo simulation and of Hα line-emission measurements. A three-dimensional neutral transport simulation has been performed by applying the DEGAS ver.63 code to the anchor region. A detailed mesh structure was built up for the three-dimensional geometry in this region and the simulation was carried out under a plausible assumption of particle source on experimental data basis. In standard Hot-Ion-Mode plasmas, a series of Hα line- emission measurements have been carried out and axial distribution of particle source rate over the region from the mirror-throat to the anchor-cell is discussed based on both calculation and measurements.