Differential cross sections for scattering of 300-500-keV ${\mathrm{H}}^{+}$,${\mathrm{He}}^{+}$, and ${\mathrm{Li}}^{+}$ on selemium in the region of weak screening

Differential cross sections for scattering of 300-500-keV ${\mathrm{H}}^{+}$, ${\mathrm{He}}^{+}$, and ${\mathrm{Li}}^{+}$ through 3-15° have been measured. The targets were 300-9000-Å-thick vacuum-deposited, self-supporting selenium foils. An empirical extrapolation procedure was used to correct for the influence of multiple scattering. The cross sections obtained agree well with the Thomas-Fermi theory, both with regard to scaling and to absolute magnitude.