Elastic backscattering of hydrogen molecules from a plasma
Neutral gas measurements in the divertors of DIII-D and JET revealed very high neutral pressures on the wall in the private flux region in excess of expectations from DEGAS simulation for DIII-D and D(alpha) intensity measured at the same position in JET. This problem may be solved if an additional scattering process between H(2) molecules and plasma ions is taken into account. This is caused by the polarisation of molecules in the field of ions and becomes important at low temperature. Its consequences are that not all neutrals starting at the wall will be absorbed by the plasma, while neutrals between plasma and wall will be heated and obtain an isotropic velocity distribution. Using a Morse-like potential, collision data for elastic scattering of H(2)-H(+) are calculated which can be used in Monte Carlo calculations.
Bibliographic Reference: Article: Journal of Nuclear Materials, Vol. 196-198 (1992) pp. 481-484
Record Number: 199310273 / Last updated on: 1994-11-29
Original language: en
Available languages: en