High-energy kinetic theory of a particle beam generated plasma

The equilibrium high-energy electron distribution in a particle beam generated plasma is calculated. The tail of the distribution, above the first excited state, is derived from a Boltzmann equation which contains inelastic collisional processes and a continuous source term. This equation is analytically solved by a Laplace transformation method and, in a numerical application for the case of an argon plasma created by a high-energy electron beam between 10³ and 10⁶eV, the branching ratios for energy deposition in ionization and excitation states are calculated. We compare the results with those of the laser group of Orsay.