INDUCED HEATING POWER EVALUATION IN RIB TRANSFER LINE OF SPIRAL2

Abstract The production of the future Radioactive Ion Beams at SPIRAL2 is studied in the case of an ECR ion source and helium as supporting gas. The RIBs transported in the transfer lines have a multi-component composition and the total current of the beams is mainly defined by helium ions. The total power of the helium component may reach 300 W. For magnetic optical elements the focusing force acting on the ions in the transfer beam line is strongly dependent on mass-to-charge ratio. For this reason the supporting gas ions will be lost at the initial part of the beam line between the ECR ion source and the analysing magnet. The helium beam losses and induced heating power density at the wall of the vacuum tube are evaluated in this report for the transport of Ar, Xe and U ion beams in the RIB transfer line of the future SPIRAL2 facility

MODIFICATION OF THE CENTRAL REGION IN THE RIKEN AVF CYCLOTRON FOR ACCELERATION AT THE H=1 RF HARMONIC

Abstract A highly advanced upgrade plan of the RIKEN AVF cyclotron is under way. The study is focused on the formulation of the new acceleration regimes in the AVF cyclotron by detailed orbit simulations. The extension of the acceleration energy region of light ions towards higher energies in the existing RF harmonic equal to 2 and the modification of the central geometry for the RF harmonic equal to 1 to allow an acceleration of protons at several tens of MeV are considered. The substantial redesign of the central electrode structure is needed to accelerate protons with reasonable values of the dee voltage. The new inflector geometry and the optimized central electrode structure have been formulated for the upgrade