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要旨:
This thesis investigates the interaction of electrons and highly charged ions in thin plasmas
with a focus on spectroscopic studies of resonant recombination processes. For this purpose, a new electron beam ion trap (EBIT) was assembled and brought into operation at the Max-Planck Institute for Nuclear Physics. This cryogenic device is also designed for fast
charge breeding and serves as a prototype for future devices used at radioactive ion beam
facilities. In its first stage electron beam currents of 550mA were reached, and an upgrade
to 5A is planned. As an initial scientific application, X-Ray spectra of di- and trielectronic
recombination into helium-like to oxygen-like silicon-ions under excitation of an electron
from n = 1 -> 2 were studied with the new EBIT. These spectra show an excellent
resolution in the projectile electron energy. A comparison with MCDF and CI calculations
shows an influence of recombination into ions in longlived, metastable states. The time
evolution of the recombination spectra is used to investigate the charge state distribution
within the trap. Along with these measurements, spectra in the region between 5nm and
12nm were recorded to diagnose the charge breeding process and to determine the effective
electron density in the EBIT plasma.
