No abstract available

[en] A small Penning-type ion source with an ion-current-neutral conversion sensitivity of 2 x 10^-2 A torr^-1 has been constructed. Ion extraction is by way of a channel in one magnet pole face where a retarding-potential plot has shown that 95% of the ions have an energy less than 100 eV. The source is utilized with a high-energy ion stop and a quadrupole mass filter with an out-of-line-of-sight ion collector. (orig.)

[en] An examination has been made of differing electron-multiplier structures in order to determine a form most suitable for miniaturization and application to the detection of positive ions in mass spectrometry. A study of equipotential patterns in the dynode inter-space of a linear array has led to the development of a compact dynode-form. A 16-stage linear electron multiplier array has shown a current gain of 4 X 10⁶ at an overall potential of 3 kV on the dynode chain. (Auth.)

[en] The pre-breakdown ionization process is investigated by mass spectroscopy of discharge species. Before the starting of the gaseous breakdown the spatial electron distribution increases. It is caused by ionization processes induced in atoms by the precursor electron flux. The products of electron impact, photo, auto and Penning ionization processes were analyzed by in-built mass spectrometer. The results depend on surface properties, electrochemistry and contamination of electrodes. (D.Gy.)

[en] A Monte Carlo model for the simulation of electron penetration into aluminium and for the generation and emission of secondary electrons is presented. Monte Carlo calculations for the penetration and backscattering of primary electrons show good agreement with experiment, while the dependence of the secondary electron yield on the primary electron energy show qualitative agreement with experimental measurements. β, which is defined as the relative efficiency of backscattered electrons for producing secondary electrons which escape the surface over that of the primary electrons on their inward path, is found to be ∼6-7 for primary electrons in the energy range 3-25 keV. (author)