Ion charge state distributions due to vacancy cascades following K-, L 1 -, L 2 -and L 3 -shell ionization are calculated using a Monte Carlo technique. Probabilities P (q) that the de-excited ions become q-fold ionized after a single primary ionization are given as a function of the atomic number in the region Z = 10-60. The calculations are accomplished by tracing successive radiative and non-radiative transitions and electron shake-off as an additional effect. Thereby, radiative and non-radiative transition rates and shake-off probabilities have been calculated from relativistic wavefunctions.

The Dresden electron beam ion trap (EBIT)/electron beam ion source (EBIS) family are very compact and economically working table-top ion sources. We report on the development of three generations of such ion sources, the so-called Dresden EBIT, Dresden EBIS, and Dresden EBIS-A, respectively. The ion sources are classified by different currents of extractable ions at different charge states and by the x-ray spectra emitted by the ions inside the electron beam. We present examples of x-ray measurements and measured ion currents extracted from the ion sources at certain individual operating conditions. Ion charge states of up to Xe(48+) but also bare nuclei of lighter elements up to nickel have been extracted. The application potential of the ion sources is demonstrated via proof-of-concept applications employing an EBIT in a focused ion beam (FIB) column or using an EBIT for the production of nanostructures by single ion hits. Additionally we give first information about the next generation of the Dresden EBIS series. The so-called Dresden EBIS-SC is a compact and cryogen-free superconducting high-B-field EBIS for high-current operation.

The ion charge state distribution in EBIS and EBIT as well as the corresponding ion current outputs from this devices are modelled for different possible trap operating modes. Thereby, for EBIS and EBIT a model was developed for the calculation of ion charge state distributions considering single and double ionization and charge exchange processes, radiative recombination and strong ion cooling. A detailed description of the model is given. A computer code based on the developed model is able to calculate EBIS and EBIT basic parameters: ion charge state spectrum, ion temperatures and output ion beam currents. Simulation results are given for nitrogen, neon, argon, krypton and uranium and are for some cases compared with available experimental data.

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