Formulas for cross sections and rate coefficients for partial electron impact ionization of CH4 and H-2

Robust, accurate, and asymptotically exact cross section formulas for all d irect and dissociative electron impact ionization channels of methane and h ydrogen are presented. The parameter estimation employs Bayesian inference and allows for a consistent use of data from different experiments with pos sibly discordant calibrations. An efficient method for the calculation of r ate coefficients and their temperature derivatives is outlined. (C) 2001 Am erican institute of Physics.