The Development of Electron Momentum Spectroscopy⁄

Electron momentum spectroscopy measures relative difierential cross sections as a function of recoil momentum for energy-resolved states of the ion in a kinematically-complete electron-impact ionisation experiment. The experiment is done in a kinematic range where correct cross sections are obtained by simple reaction approximations. It amounts to a measurement of orbital momentum densities and coe–cients describing electron correlations in the ion for most ion states of a gas target. Certain ion states give information about ground-state correlations. For a solid target it amounts to a measurement of the energy{momentum density of occupied electron bands. 1