| Paper | Title | Page |
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| TUPAS053 | Beam Dynamics Studies for the Reacceleration of Low Energy RIBs at the NSCL | 1769 |
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Funding: This work is supported by the U. S. Department of Energy Rare Isotope Beams (RIBs) are created at the National Superconducting Cyclotron Laboratory (NSCL) by the in-flight particle fragmentation method. A novel system is proposed to stop the RIBS in a helium filled gas system followed by reacceleration that will provide opportunities for an experimental program ranging from low-energy Coulomb excitation to transfer reaction studies of astrophysical reactions. The beam from the gas stopper will first be brought into a Electron Beam Ion Trap (EBIT) charge breeder on a high voltage platform to increase its charge state and then accelerated initially up to about 3 MeV/u by a system consisting of an external multi-harmonic buncher and a radio frequency quadrupole (RFQ) followed a superconducting linac. The superconducting linac will use quarter-wave resonators with bopt of 0.047 and 0.085 for acceleration and superconducting solenoid magnets for transverse focusing. The paper will discuss the accelerator system design and present the end-to-end beam dynamics simulations. |
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| TUPAS054 | Design Studies of the Reaccelerator RFQ at NSCL | 1772 |
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| Rare Isotope Beams (RIBs) are created at the National Superconducting Cyclotron Laboratory (NSCL) by the in-flight particle fragmentation method. A novel system is proposed to stop the RIBS in a helium filled gas system followed by a reacceleration that will provide opportunities for an experimental program ranging from low-energy Coulomb excitation and to transfer reaction studies of astrophysical reactions. The beam from the gas stopper will first be brought into a Electron Beam Ion Trap (EBIT) charge breeder on a high voltage platform to increase its charge state and then accelerated initially up to about 3 MeV/u by a system consisting of an external multi-harmonic buncher and a Radio Frequency Quadrupole (RFQ) followed a superconducting linac. The planned RFQ will operate in the cw mode at a frequency of 80.5MHz to accelerate ion beams from ~12 keV/u to ≥ 300keV/u. An external multi-harmonic buncher will be used to produce a small longitudinal emittance beam out of the RFQ. In this paper, we will describe the design of the RFQ, present the beam dynamics simulation results, and also discuss the impact of the external buncher harmonics on the output beam properties. | ||
| TUPAS055 | End-to-End Beam Dynamics Simulations of the ISF Driver Linac | 1775 |
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| A proposed Isotope Science Facility (ISF), a major upgrade from the Coupled Cyclotron Facility at the National Superconducting Cyclotron Laboratory (NSCL), will provide the nuclear science community with world-class beams of rare isotopes. The ISF driver linac will consist of a front-end and three acceleration segments of superconducting cavities separated by two charge-stripping sections, and will be capable of delivering primary beams ranging from protons to uranium with variable energies of ≥200 MeV/nucleon. The results of end-to-end beam simulation studies including physical misalignments, dynamic rf amplitude and phase errors, and variations in the stripping foil thickness, will be performed to evaluate the driver linac overall performances and beam loss, even for the challenging case of the uranium beam with multiple charge states using the newly-developed RIAPMTQ/IMPACT codes. The paper will discuss ISF beam dynamics issues and present the end-to-end beam simulation results. | ||
| THPAS051 | The RIAPMTQ/IMPACT Beam-Dynamics Simulation Package | 3606 |
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Funding: This work is supported by the U. S. Department of Energy, DOE contract number:W-7405-ENG-36 RIAPMTQ/IMPACT is a pair of linked beam-dynamics simulation codes that have been developed for end-to-end computer simulations of multiple-charge state heavy-ion linacs for future exotic-beam facilities. The simulations can extend from the low-energy beam transport after the ECR source to the end of the linac. The work has been performed by a collaboration including LANL, LBNL, ANL, MSU, and TechSource. The code RIAPMTQ simulates the linac front end including the LEBT, RFQ, and MEBT, and the code IMPACT simulates the main superconducting linac. The codes have been benchmarked for rms beam properties against previously existing codes at ANL and MSU. The codes allow high-statistics runs on parallel supercomputing platforms, such as NERSC at LBNL, as well as runs on desktop PC computers for low-statistics design work. We will show results from 10-million-particle simulations of RIA designs by ANL and MSU, carried out at the NERSC facility. These simulation codes will allow evaluations of candidate designs with respect to beam-dynamics performance including beam losses. |