Large-angle elastic resonant and nonresonant scattering of electrons fromB3+(1s2)andB4+(1s)ions: Comparison of experiment and theory

Abstract

High-resolution doubly differential cross section measurements and calculations for electrons elastically scattered through $180\ifmmode^\circ\else\textdegree\fi{}$ from ground-state He- and H-like boron ions are presented covering the entire ${1s2lnl}^{\ensuremath{'}}$ (for ${\mathrm{B}}^{3+})$ and ${2lnl}^{\ensuremath{'}}$ (for ${\mathrm{B}}^{4+})$ Rydberg series populated by resonant excitation. The measurements were performed by zero-degree Auger projectile electron spectroscopy of 4-MeV ${\mathrm{B}}^{3+,4+}$ ions in collisions with ${\mathrm{H}}_{2}$ targets. R-matrix calculations, particularly sensitive at this large scattering angle to electron correlation, exchange, and interference effects, are found to be in excellent overall agreement within the electron-scattering model.