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キーワード:
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要旨:
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.
