As a part of SPIRAL1 upgrade, experimental studies were carried out to understand the ion transport through the SP1 ECR charge breeder and to investigate the physical mechanisms involved in charge breeding process . Numerical simulations were performed using SIMION 3D to reproduce the trends of low charge states (1+ and 2+) experimental results (charge breeding efficiency versus ∆V curves) by transporting the 1+ ion beam through a potential map that reflects the presence of the ECR plasma (without collisions) . The simulations results showed good agreement with the experiments and revealed the role of Coulomb collisions in the charge breeding process leading to a necessary detailed analysis using a full six-dimensional (6D) phase space Monte-Carlo Charge Breeding code (MCBC) [2, 3].
The simulation code models Coulomb collisions of the injected 1+ ion beam in an ECR plasma and atomic processes which includes ionization and charge exchange. The background ECR plasma has been modeled by implementing a simplified plasma model scheme, proposed in the previous charge breeding simulation studies [4, 5]. The charge breeding simulations were performed for three experimental cases (interaction of Na1+ with a helium plasma, K1+ with a helium plasma and K1+ with an oxygen plasma). The model finally able to reproduce the low charge state (1+ and 2+) experimental trends by varying each plasma parameter (plasma density, ion temperature and electron temperature) independently. Finally, the estimated plasma parameters obtained from each case are presented and the reasons for the difference in charge breeding efficiencies between Na and K species are discussed.
 A. Annaluru et al., “1+/N+ method: numerical simulation studies and experimental measurements on the SPIRAL1 ECR Charge Breeder”. Journal of Instrumentation. 14. C01002-C01002. 10.1088/1748-0221/14/01/C01002.
 J. S. Kim, L. Zhao, B. P. Cluggish and Richard Pardo, "Ion beam capture and charge breeding in electron cyclotron resonance ion source plasmas", Rev. Sci. Instrum., 78, 103503 (2007).
 L. Zhao, B. P. Cluggish, J. K. Kim, R. C. Pardo and R. C. Vondrasek, "Simulation of charge breeding of rubidium using Monte Carlo charge breeding code and generalized ECRIS model", Rev. Sci. Instrum., 81, 02A304 (2010).
 A. Galata, D. Mascali, L. Neri and L. Celona, "A new numerical description of the interaction of an ion beam with a magnetized plasma in an ECR based charge breeding device", Plasma Sources Science and Technology. 25. 10.1088/0963-0252/25/4/045007.
 V. Mironov, S. Bogomolov, A. Bondarchenko, A. Efremov, V. Loginov, "Simulations of charge-breeding processes in ECRIS", AIP Conference Proceedings 2011, 070003 (2018).
|Category of your contribution||Radioactive ion beam sources and charge breeders|