FLUX LIMITING DUE TO ELECTRON-IMPACT EXCITATION-ENERGY LOSS

Large radiation losses in the electron energy balance equation due to electron impact excitation can cause the parallel scale length to beco me small enough that a short mean-free path expansion becomes question able for the high-speed tail electrons. It then becomes necessary to l imit the parallel electron heat flux so that it remains below its free -streaming value nT(3/2)/m, where n, T, and m are the electron density , temperature, and mass. A Boltzmann inelastic scattering collision op erator is adopted to investigate whether electron impact excitation ca n lead to a self-consistent flux limit by depleting the electron tail. (C) 1996 American Institute of Physics.