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Other Keywords |
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MOOBMH02 |
Emittance Measurements For RIKEN 28 GHz SC-ECRIS |
ion, extraction, ion-source, experiment |
10 |
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- Y. Higurashi, T. Nakagawa, J. Ohnishi, K. Ozeki
RIKEN Nishina Center, Wako, Japan
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In 2013, the intense beams of highly charged uranium ion (180euA of U35+, 230euA of U33+) were extracted from RIKEN SC-ECRIS. Following the success, intense beam of U35+ ions was used for the RIBF experiment for 24 days without break. It is obvious that production of high-quality beam (smaller emittacne and good stability etc) is also important for RIKEN radio isotope beam factory (RIBF) project. For this reason, in 2014, we systematically measured the emittance and beam intensity of the highly charged uranium ions under various conditions (magnetic field configuration, extracted beam intensity, beam stability etc) to search the optimum condition. In these experiments, we observed that the emittnce size is strongly dependent on the magnetic field configuration, especially Bext. In this contribution, we present the effect of the various parameters (magnetic field configuration, extracted beam intensity, beam stability etc) of the SC-ECRIS on the beam intensity and emittance. We also discuss its mechanism in detail.
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Slides MOOBMH02 [2.472 MB]
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MOOAMH03 |
Optimization Of Low-Energy Beam Transport |
ion, solenoid, ECRIS, dipole |
33 |
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- H.R. Kremers, J.P.M. Beijers, S. Brandenburg
KVI, Groningen, The Netherlands
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We have studied the extraction and transport of a low-energy ion beam between an Electron Cyclotron Resonance (ECR) Ion Source and the analyzing magnet. This first part of the transport line is particularly sensitive to emittance blowup caused by ion-optical aberrations and non-paraxiality of the beam. This can be prevented by an appropriate focussing element between ion source and analyzing magnet. We present the results of beam transport simulations for different focussing elements including an einzel lens, solenoid and quadrupole element. These calculations, verified by measurements, lead to a design of an optimal, low-energy beam transport line for ion beams with large beam divergences.
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Slides MOOAMH03 [2.910 MB]
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MOOAMH05 |
Combination of Two ECRIS Calculations: Plasma Electrons and Extracted Ions |
electron, ion, plasma, simulation |
38 |
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- S. Biri, R. Rácz
ATOMKI, Debrecen, Hungary
- R. Lang, J. Mäder, F. Maimone, B.R. Schlei, P. Spädtke, K. Tinschert
GSI, Darmstadt, Germany
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In strongly magnetized ECRIS plasmas collisions do not influence the path of the charged particle. Electrons and ions can move more freely only along the magnetic field line compared to the transverse direction. Extraction simulation requires that the trajectories of charged particles have to be traced through the plasma chamber. In previous simulations the particle density at the beginning of the trajectory deep inside the plasma has been unknown. Now the full 3D electron tracking within the plasma chamber has been combined with the generation of initial ion starting conditions including particle density for ion tracking. The TrapCAD code has been used to determine the electron spatial distribution in a certain energy window. The idea is that at the places where the electron reaches a specific energy, an ion trajectory can be started. The magnetic field has been modeled with OPERA. The computer code KOBRA3-INP has been used for ray tracing. First results will be discussed and compared with experimental experience. The number of affecting parameters on the operating conditions of the ion source may lead to a multi-dimensional optimization space for simulation.
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Slides MOOAMH05 [10.655 MB]
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MOPPH007 |
Current Developments for Increasing the Beam Intensities of the RIKEN 18-GHz Superconductiong ECR Ion Source |
ion, ECRIS, ion-source, cyclotron |
57 |
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- T. Nagatomo, V. Tzoganis
RIKEN, Saitama, Japan
- O. Kamigaito, M. Kase, Y. Kotaka, T. Nakagawa
RIKEN Nishina Center, Wako, Japan
- Y. Kotaka
SHI Accelerator Service Ltd., Tokyo, Japan
- Y. Ohshiro
CNS, Saitama, Japan
- V. Tzoganis
The University of Liverpool, Liverpool, United Kingdom
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Providing intense and highly charged heavy ion beams is one of the most essential and fundamental technologies to explore a trackless frontier so-called “Island of Stability” where relatively stable super heavy elements are considered to exist. Towards this goal, the development of an ion source that can provide a highly charged heavy ion beam with high intensity and low emittance is necessary. In order to provide the desired high intensity ion beam, the beam-radius expansion induced by space charge effects cannot be ignored, and it can cause considerable degradation of the beam emittance. To suppress such effects at the output of an ion source is one of the top priorities in the direction of improving both the quality and intensity of the beam. At first, we plan to examine the space charge effects with a high-intensity beam provided by the 18-GHz Superconducting ECR Ion Source at RIKEN Nishina Center. To measure the degradation of the beam emittance as function of the beam’s intensity, an in-situ emittance monitor system based on the pepperpot technique and applicable to a wide range of beam intensities is being developed. A report on the current status will be presented.
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