Electron momentum spectroscopy of metals

Electron momentum spectroscopy measurements of aluminum, copper and gold are presented. Data were taken for incoming electrons with an energy of 50 keV, and both outgoing electrons with an energy near 25 kcV. In all cases we used an identical deconvolution procedure, which consistently removes all intensity at high energy loss values. However the intensity becomes vanishing small only for binding energies of about twice the bandwidth. The observed spectra compare well with many body calculations based on the cumulant expansion scheme.