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Notes: Measurements of bremsstrahlung down to 7 keV emitted from a 7.25 GHz electron cyclotron resonance discharge and the deconvolution of the spectra using a newly developed integration method yield the exact electron distribution function. Two separate electron populations with temperatures about 3 and 25 keV and with densities about (0.2...4)108 cm−3 were recorded. First, results are obtained for the behavior of these populations belonging to the mixture (argon–oxygen–hydrogen). Gas mixing increases the densities of these populations, but hardly changes the temperatures. © 1995 American Institute of Physics.

Notes: A pinhole camera with an x-ray sensitive charge-coupled device array was used to analyze x-rays emitted from an electron cyclotron resonance (ECR) discharge. The camera was operated at a temperature of 140 K, allowing single photon detection at integration times up to several hours. This technique simultaneously allows spectroscopic investigations as well as x-ray imaging. Thus, the geometrical size and x-ray emission profiles from an ECR plasma were measured. © 1996 American Institute of Physics.

Notes: Characteristic x-ray lines of heavy ions are used as threshold indicators for the number of plasma electrons with an energy higher than the orbital electron binding energy of the initial vacancy for the corresponding x-ray transition. For heavy ion plasmas the intensity ratio between x-ray lines of different series shows how the mean energy of the electron changes with the operating conditions of an electron cyclotron resonance ion source. With the combination of line intensity and bremsstrahlung measurements, information on the anisotropy of the electron energy distribution function is obtained. Characteristic and continuous radiation is recorded at the same time and with the same apparatus. Therefore, errors are extremely small. © 1996 American Institute of Physics.

Notes: The injection of an additional strong focused electron beam from a special designed electron gun into a magnetic electron cyclotron resonance (ECR) confinement field is studied. The electron gun uses a cathode with a long lifetime and resistiveness providing high emission current densities with electron currents up to 50 mA and voltages up to 4 keV. A sequence of aluminum foils is used to investigate the trajectories of the electrons in the magnetic field without plasma. The high density electron beam passes through the foils, welds them, and prints its image into the foils. Details of this technique are described in Ref. 1. Using this technique we see that before the electrons enter the sextupole region the beam moves along the magnetic straight lines preserving its structure. Only a central beam passes through the sextupole region, thereby changing its form due to the interaction with radial components of the magnetic field. A new operation method at our 14.5 GHz ECR ion source is based on so-called reflection mode electrons (RMEs) analogous to a known electron beam ion source operation regime.2 The basic idea is that electrons, which traveling from the cathode in a strong axial field, meet an anticathode potential, are reflected from it, move back to the cathode, and will be reflected again and so on. It can be supposed that the electrons will make reflections up to the moment when the anode aperture of the gun is fulfilled and the electrons will be collected on the anode electrode. Investigations are performed extracting nitrogen ions using the RME beam. As a result we got a clear increase in the beam current of the extracted ions (e.g., at 10 mA electron injection an increase of the current of N5+ ions up to 400%) and a shift of the measured ion charge state distribution to higher mean ionization stages. Measured x-ray spectra from a neon loaded plasma show for the case of RME operation increasing energy shifts to the high energy side of the spectra, i.e., the mean ionization degree of the ions in the plasma increases. They also increase the intensity of the neon K x rays (more than 100% increase for RME injection of Ee=4 keV and Ie=10 mA) indicating that for the same operation parameters the mean density of energetic electrons rises at RME injection, i.e., there are more electrons with energies high enough to ionize K-shell electrons in neon. © 2000 American Institute of Physics.

Notes: Wavelength dispersive x-ray measurements on cobalt and krypton ions were presented to determine the ion charge state distribution (CSD) inside the electron cyclotron resonance (ECR) plasma of the 14.5 GHz ECR ion source of the TU Dresden. For clearly from the parent diagram lines separating x-ray satellites a comparison between calculated wavelength shifts and measured ones allows it to deduce the ion CSD of the analyzed ions. In the case of small line shifts (lower ionization states) a comparison with x-ray spectra derived from plasma modeling is done. By approximating the modeled spectra to the measured ones a most probable ion CSD was derived. © 1998 American Institute of Physics.

Notes: High charge states of heavy ions inside the electron cyclotron resonance plasma are produced by hot and warm electrons with energies above 3 keV. The slope of the electron energy distribution function and the density of these populations were obtained from bremsstrahlung spectra emitted by the 7.5 GHz Electron Cyclotron Resonance Ion Source of the Forschungszentrum Rossendorf measured with a HP Ge solid state detector. For this a new deconvolution method has been used. The operating condition of the ion source influences the behavior of the electrons. Mixing in of light gases to the discharge strongly increases the electron density. © 1996 American Institute of Physics.

Notes: A 14.6-GHz electron cyclotron resonance ion source has been designed and will be installed at the TU Dresden. Contrary to other ECR sources some features are foreseen for atomic physics experiments to study the source plasma. Beside the description of source construction and computer-aided source control first physical experiments on the source are discussed.

Notes: A MIVOC system as it has been applied to several electron cyclotron resonance ion sources has been used to load a room temperature electron beam ion trap with a selection of different metals. X-ray measurements have demonstrated the ability of this method to produce highly charged ions for a large number of elements in a simple way and at low costs, which is favored by the low consumption rate of the used substances and operation of the ion trap at room temperature. The analysis of x-ray spectra measured with a Si(Li) semiconductor detector which is based on atomic structure calculations indicate the production of Mn23+, Fe25+, Ge30+, and Sn44+ ions. © 2000 American Institute of Physics.

Notes: 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. © 2000 American Institute of Physics.

Notes: A compact warm electron beam ion trap (WEBIT) is described and investigated experimentally. The trap design is based on permanent magnets, an electron gun with a cathode emissivity of 25 A/cm2 and a gun perveance of 0.1 μA/V3/2 as well as a vacuum vessel allowing trap operation at pressures of 10−10 Torr. The electron beam diameter measured with a pinhole camera was 160 μm corresponding to an electron beam density of 248 A cm−2. X-ray spectra measured with a Si(Li) semiconductor detector indicate the production of Xe44+ and Ir59+. © 1999 American Institute of Physics.