Electron-energy-loss experiments on calcium, strontium and barium

Electron-energy-loss experiments on thin films of Ca, Sr and Ba performed with 50 keV electrons are reported. The energy loss function is derived from the spectra and further the dielectric functions epsilon 1 +i epsilon 2 of these metals are determined in the energy range of 2-50 eV. The dispersion of the losses as well as the dependence of its half-widths on the wave-vector has been determined. The results are compared with those of other authors.