Monte Carlo Simulation of Electron Swarm in a Model Gas: Transverse and Longitudinal Diffusion Coefficients

The Monte Carlo simulation (MCS) of the electron swarm in a model gas with the momentum-transfer cross section of the form σ m (ε)∝ε γ (γ=-0.5, 0, and 1), ε being the electron energy, is carried out in order to investigate the recent question raised, in particular, for γ=1 about the conventional two-term expression for the transverse diffusion coefficient D T . The MCS results confirm that the two-term solution of D T (and other swarm parameters) is sufficiently accurate even for γ=1 contrary to the recent doubt; a possible reason for the discrepancy previously revealed between the MCS and two-term values of D T is suggested. The scaling rule for the electron swarm in rare gases derived on the basis of the two-term approximation of the Boltzmann equation in order to reduce the MCS computation time is verified to be valid.