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Abstract

Deceleration is required to produce multicharged ion beams in the energy range from few keV to few MeV. It should be noted that the idea of decelerating ions in storage rings to lower energies dates back to H. Poth (1990). During deceleration of the charged particle beam, the influence of residual gas interaction, intrabeam scattering (IBS) as well as the incoherent space charge tune shift increase. These phenomena are mostly dominant in storage rings and become important at low velocities. The purpose of this PhD thesis is the generation of low-velocity ion beams by deceleration at the heavy ion cooler storage ring TSR and the study of the accompanying processes. Deceleration experiments concentrated on ¹²C⁶⁺ ions to identify the mechanisms which have an influence on the behavior and evolution of the beam. To explore the deceleration cycle, the ¹²C⁶⁺ ions are decelerated from 73.3 MeV to 9.77 MeV with an efficiency of 90%. To achieve this low energy two cooling steps at the initial andfinal energies of the beam are applied. Electron pre-cooling results in a dense ion beam where IBS has to be taken into account to describe the development of beam size during deceleration. An approximated model of IBS is proposed to interpret the experimental data. A decrease of the ion beam revolution frequency during the deceleration cycle reduces the beam current, which makes it difficult to measure with a common current transformer. Hence, new techniques are applied at low ion currents to determine the stored number of particles. Also incoherent tune shift effects, limiting the maximum number of stored particles are investigated. The availability of low-energy ion beams will expand the range of multicharged beam energies for precision studies of ion-atom collision in-ring MOT-Remi experiments.