Total Cross Sections for Inelastic Scattering of Charged Particles by Atoms and Molecules. II. Negative Hydrogen Ion

Abstract

The sum rule for the Bethe inelastic-scattering cross sections is applied to the negative hydrogen ion, for which it yields the asymptotic total cross section for electron detachment by charged-particle impact. The calculation requires knowledge of two properties of ${\mathrm{H}}^{-}$: the incoherent-scattering function, which is computed from several different ground-state wave functions, and the oscillator-strength distribution, which is deduced from a variety of experimental and theoretical data. The resulting detachment cross section for electron impact, including all final H-atom states, is ${\sigma }_{\mathrm{tot}}=4\mathrm{}{{\pi }_0}^2\left(\frac{R}{T}\right)\left[7.\mathrm{}484\ln \right(\frac{T}{R})+25.3\mathrm{}\pm 1.5]$, where $a_0$ is the Bohr radius and $\frac{T}{R}$ the incident energy in rydbergs. Our result is consistent with the experimental data of Dance, Harrison, and Rundel, but incompatible with those of Tisone and Branscomb. A tabulation of the incoherent-scattering function and the atomic form factor is also given.