S. Landgraf

Dresden EBIT: Results and perspectives

The Dresden electron-beam ion trap (EBIT) is a long-term stable room-temperature EBIT working without any cryogenic techniques. Spectroscopic investigations have shown that in the Dresden EBIT bare nuclei at least up to nickel can be produced as well as helium-like ions from elements such as krypton or germanium and neon-like ions from elements such as xenon or iridium. The output of quantum radiation from highly charged ions trapped in the Dresden EBIT is high enough that wavelength-dispersive spectroscopic investigations are possible. Up to now, two devices (Dresden EBIT I and Dresden EBIT II) have been built up. Results derived on Dresden EBIT II demonstrate that it is possible to produce the described apparatus in any number. Thus, it opens up a way also for small laboratories to employ highly charged ions in their investigations.

Highly charged ions produced in a warm electron beam ion trap

A compact electron beam ion trap (WEBIT) working at room temperature without any cryogenic components is described and experimentally investigated. The trap design is based on permanent magnet technology. For the formation of the electron beam a Pierce electron gun equipped with a cathode of high emissivity is used. The ion trap is created by a compressed electron beam passing through a drift tube system consisting of three sections with corresponding electrical trap potentials. X-ray spectra measured with a Si(Li) semiconductor detector indicate the production of Kr34+, Xe44+, Ce48+, Ir64+, and Hg66+ ions.

A novel room temperature electron beam ion trap for atomic physics and materials research

Abstract Highly charged ions are used in basic investigations to study problems in atomic and plasma physics. Further on, the application of highly charged ions in materials research and other fields as nanomechanics and information techniques grew significantly in the last years. In the present paper, we report on results derived with a warm electron beam ion trap (WEBIT) that works without any cryogenic equipment. A special source construction allows to generate dense electron beams at room temperature with a current density of up to 240 A cm−2 and an acting ionization factor of (2⋯5)×10 21 cm −2 . Ions like Ar17+, Xe44+ and Ir65+ were detected by X-ray spectroscopy. A charge capacity of about 8×107 elementary charges of the trap is estimated.

Dresden electron beam ion trap: Status report and next developments

The Dresden EBIT is a room-temperature EBIT producing highly charged ions for x-ray spectroscopy as well as for materials modifications and other applications. In the past we have demonstrated the production of ions such as Ar18+, Fe26+, Kr35+, Xe46+, and Ir67+. Here we give a report on the further development of this ion source to increase the electric trap capacity involving the production of a greater amount of highly charged ions.

X-ray spectroscopy and ion extraction at the Dresden EBIT

Abstract The Dresden electron beam ion trap (EBIT) is a compact, long-term stable room-temperature EBIT able to produce bare nuclei for elements up to about Z =30 and helium-like to neon-like ions for heavier elements, respectively. With ion species ranging from Ir 57+ up to Ir 62+ and Ce 48+ we demonstrate the applicability of the ion source for energy and wavelength-dispersive X-ray spectroscopy. First ion extraction experiments show that it is possible to extract ion currents of 10 6 ions per pulse at various pulse repetition rates, measured electrically for xenon ion pulses with a mean ion charge of Xe 40+ and a pulse FWHM of 15 μs. Additionally, first X-ray spectra from the interaction of extracted xenon ions with a carbon target are presented.

First investigations on the Dresden EBIS-A

We present first experimental investigations on the Dresden EBIS-A, an advanced design of the Dresden EBIT. The Dresden EBIS-A, an EBIT machine working at roomtemperature is equipped with a NdFeB ring magnet system producing a magnetic field on axis of about 620 mT. The measurement of integral ion pulses from the ion source yield a number of extracted elementary charges in the order of 109 per ion pulse. It is shown that the width of the ion pulse can be changed from microseconds up to several tens of microseconds varying the potential of the third drift tube section. The measurement of separated charge states provides an indication of an increased ion output compared to that of the Dresden EBIT. X-ray spectra account for the production of ions such as Ar17+, Xe44+ and Ce49+in the electron beam of the ion source.

Time-resolved investigation of ionization processes in the Dresden Electron Beam ion Source

The emission of characteristic x-ray lines of iron and krypton ions was measured in dependence on the confinement time in an Electron Beam Ion Source, the DRESDEN EBIS. Primarily the measurement was focused on x-ray lines from dielectronic recombination (DR) processes. Due to the sharp resonant character of DR processes the formation of individual ion charge states can be observed at different electron energies (resonance energies) with time-resolved energy-dispersive x-ray spectroscopy. In the case of iron ions, experimentally observed resonance energies are compared to resonance energies calculated with the Flexible Atomic Code (FAC). Further, on outer-shell Kα x-ray satellites of krypton ions are time-resolve analyzed to construct the evolution of the ionization of krypton ions in the electron beam.

Report on the current developments and experiments of the Dresden EBIT System

The developmental direction of the Dresden EBIT system is being supplemented by a new model, the Dresden EBISA. A short review of the development history and an outline of the status will be given. Recent measurements of time-resolved and energy-dispersive X-ray spectroscopy are presented with focus on the dielectronic recombination resonances of krypton.