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.

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The evolution of the charge state distribution inside an electron beam ion source or trap (EBIS/T) is determined by interactions of the electron beam with the ions in the trap region. Hence, detailed information about the electron beam is required for evaluations of spectroscopic and ion extraction measurements performed at EBIS/T facilities. This article presents the results of investigations on the electron beam properties of an ion source of the Dresden EBIS type. For the first time theoretical predictions of the shape of the beam were tested for a noncryogenic EBIS working with low magnetic flux densities provided by permanent magnets. Position and width of the electron beam were measured at different electron energies showing an oscillation in the beam structure. At an energy of E(e)=16 keV and an emission current of I(e)=30 mA the beam is compressed to a radius of r(e)=57 mum (80% current). This refers to an average current density of j(e)=232 A/cm(2).

We give an overview about latest developments and measurements with the Dresden electron beam ion source family as compact and economically working table-top sources of highly charged ions. The ion sources are potential tools for various applications such as for use in combination with accelerators in medical particle therapy, as charge breeder or ion trap injector, as ion sources for a new generation of focused ion beam devices and for applications together with time-of-flight secondary mass spectrometers.

The Dresden EBIS-SC is a new superconducting EBIS designed for applications in medicine, basic research and other fields. After mechanical construction and a longer installation period first experiments have been accomplished to understand the source behavior and to get a well-founded sense about the working characteristics of the ion source. In a first step electrical properties were investigated and it was shown that the source works stable over a period of several days with electron beam currents I e of up to 500 mA at an electron beam transmission of better than 0.999 I e . Actually using a cathode of 1.5 mm the source reaches electron beam currents up to 750 mA. All measurements were performed at magnetic fields of 6 T. First ion extraction experiments demonstrate that the H + 2 output at a pulse repetition frequency of 330 Hz and an electron beam current of 300 mA is higher than 1 × 10 8 ions per pulse. This output is sufficient for medical applications, e.g. in so-called CYCLINACs. Furthermore, the corresponding DC beam was measured to about 1 eµA. The beam emittance of extracted carbon ions was determined to (7. . . 25) mm mrad. Extracted ion pulses show pulse FWHM in the order of (4 . . . 12) µs. In this paper first ion extraction spectra of highly charged carbon, argon and xenon ions are presented for different source operation regimes. Additionally energy-dispersive measured X-ray spectra from argon and xenon ions are shown and discussed. KEYWORDS: Instrumentation for particle-beam therapy; Instrumentation for particle accelerators and storage rings -low energy (linear accelerators, cyclotrons, electrostatic accelerators); Ion sources (positive ions, negative ions, electron cyclotron resonance (ECR), electron beam (EBIS))