| Paper | Title | Page |
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| MOPCP083 | Vacuum Simulation for Heavy Ion Beams in the AGOR-Cyclotron | 221 |
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Funding: This work is supported by the European Union through EURONS, contract 506065 and the "Stichting voor Fundamenteel Onderzoek der Materie" (FOM). The vacuum in the AGOR cyclotron and thereby the beam transmission is beam intensity dependent for heavy ions. The onset of significant vacuum and transmission degradation is dependent on the ion species and final energy. For 20Ne6+ @ 23 MeV/A no significant effects are observed for intensities up to at least 2 x 1012 pps, while for 206Pb27+ @ 8.5 MeV/A degradation sets in at around 1011 pps. This process is driven by the loss of particles through charge exchange with the residual gas and subsequent desorption from the chamber walls induced by the lost particles. We are developing a model based on particle tracking simulations of beam particles after charge exchange and 3D vacuum simulation including the experimentally determined 'regular' out gassing and induced desorption. An experimental setup to measure beam induced desorption was built and tested. It will be used to evaluate the mitigation measures such as surface treatment and stimulated out gassing. Improvement of the vacuum in the injection line, which is limiting the overall transmission, is also presented. |
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