A Numerical Approach to the Frequencies and Damping Rates of Ion-Acoustic Waves in Ion-Collisional Plasmas

A numerical solution to the linearized ion Fokker-Planck equation is presented for large ionization-temperature ratio ZT_e/T_i ( ≥32). By reducing the equation to an eigenvalue problem through the moment approach, the frequencies and damping rates of ion-acoustic waves in ion-collisional plasmas are calculated as well as the specific heat ratios. Comparing our results with those calculated by Tracy et al. Phys. Fluids, B5 (1993) 1430 shows that our method is accurate enough in large ZT_e/T_i plasmas.