Higher order approximations of the transmission and escape probability method for neutral particle transport in edge plasmas

Higher order approximations, which take into account the effects of angular anisotropy, spatial nonuniformity and energy dependence of the distribution of neutral particles, have been developed and implemented to extend the range of validity of the transmission and escape probabilities (TEP) method for the calculation of neutral particle transport in plasmas. Comparisons with Monte Carlo calculations of model test problems and DIII-D [J. Luxon, Nucl. Fusion, 42, 614 (2002)] L- and H-mode discharges show that these new extensions significantly improve the accuracy and extend the range of validity of the TEP methodology. (c) 2006 American Institute of Physics.