Evolution of a Maxwellian plasma driven by ion‐beam‐induced ionization of a gas

摘要: The ionization of gas by intense (MeV, kA/cm2) ion beams is investigated for the purpose obtaining scaling relations rate rise electron density, temperature, and conductivity resulting plasma. Various gases including He, N, Ar at pressures order 1 torr have been studied. model local assumes a drifting Maxwellian distribution. In limit that beam to density ratio small, initial stage occurs on impact time lasts few nanoseconds. Thereafter, neutrals thermal electrons dominates production. does not grow exponentially, but proceeds linearly fast scale tth=U/(vbρ dE/dx) associated with taken lose energy U via collisional stopping in gas, where potential vb velocity, ρ mass dE/dx power units eV cm2/g. T...