Au L α and L β and Ag L-shell x-ray production cross-sections by electron impact have been measured in the incident energy region from near threshold to about 25 keV. Thin films with thick aluminium substrates were used as targets in the experiments. The effect of directional and energy spreading of the electron beam within the active films and x-ray enhancement due to backscattering electrons and bremsstrahlung photons from the substrates are corrected by means of Monte Carlo simulations. The corrected experimental data provided by this method are compared with calculated cross-sections from a PWBA theory with Coulomb, relativistic and exchange corrections and with other experimental data available in the literature.

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A high-quality electron beam with a central energy of 0.56 GeV, an energy spread of 1.2% rms, and a divergence of 0.59 mrad rms was produced by means of a 4 cm ablative-capillary-discharge plasma channel driven by a 3.8 J 27 fs laser pulse. This is the first demonstration of electron acceleration with an ablative capillary discharge wherein the capillary is stably operated in vacuum with a simple system triggered by a laser pulse. This result of the generation of a high-quality beam provides the prospects to realize a practical accelerator based on laser-plasma acceleration.

The measurement of Lα, Lβ x-ray production cross sections for the element Pb (Z = 82) by 16–40 keV electron impact is reported in this paper. The target used in the experiment was prepared by evaporating the elemental Pb onto a thick pure carbon substrate. The effects of multiple scattering of electrons when penetrating the target film, of electrons reflected from the thick pure carbon substrate and of bremsstrahlung photons produced by the impact of incident electrons on the target are corrected using the Monte Carlo method. The experimental data, reported here for the first time in the energy region of interest, are compared with the plane-wave Born approximation theory with exchange, Coulomb and relativistic corrections. They are in good agreement.

Electron impact Sc and V K-shell ionization cross sections have been measured for the first time in the incident energy region from near threshold to 45 keV. Thin targets with thick substrates are used in the experiments. The influence of the substrate on measured data has been corrected by a method based upon an electron transport calculation. For Sc and V elements, the experimental data are compared with some empirical formulae and theoretical results. It is found that the experimental data for Sc and V and most of the other elements measured before (i.e. Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Nb and Mo) with the same method as presented in this paper, can be reasonably described by both Luo's theoretical results and Casnati's empirical formula.