Monte Carlo Study of a Hydrogenous Plasma near the Ionization Temperature

Results of a recent Monte Carlo study of a hydrogenous plasma near the ionization temperature show that distribution functions obtained are unusually sensitive to two parameters. The first is the cutoff imposed at small radii on the Coulomb potential between unlike particles, and it becomes necessary to consider quantum-mechanical effects at these radii. The second is the maximum step length $\Delta$ through which the particles are allowed to move in the Monte Carlo procedure. It appears that near the ionization temperature the plasma behaves as a mixture of two phases, one ionized, the other un-ionized, and the magnitude chosen for $\Delta$ influences which phase dominates.