NSCL, East Lansing, Michigan
IAP, Frankfurt am Main
Rare isotope beam (RIB) accelerator facilities provide rich research opportunities in nuclear physics. The National Superconducting Cyclotron Laboratory (NSCL) at Michigan State University (MSU) is constructing a RIB facility, called ReA3. It will provide unique low-energy rare isotope beams by stopping fast RIBs and reaccelerating them in a compact linac. ReA3 comprises gas stopper systems, an Electron Beam Ion Trap (EBIT) charge state booster, a room temperature radio frequency quadrupole (RFQ), a linac using superconducting quarter wave resonators (QWRs) and an achromatic beam transport and distribution line to the new experimental area. Beams from ReA3 will range from 3 MeV/u for heavy ions to about 6 MeV/u for light ions, as the charge state of the ions can be adjusted by the EBIT. ReA3 will initially use beams from NSCL's Coupled Cyclotron Facility (CCF). Later ReA3 will provide reacceleration capability for the Facility for Rare Isotope Beams (FRIB), a new national user facility funded by the Department of Energy (DOE) that will be hosted at MSU. The ReA3 concept and status of ReA3 will be presented, with emphasis on the comissioning of the facility, which is underway.
GSI, Darmstadt
IAP, Frankfurt am Main
The GSI linear accelerator UNILAC provides heavy ion beams at Coulomb barrier energies for search and study of super heavy elements. Typical cross-sections of 55 fb require beam doses of 1.4·1019 according to a beam time of 117 days. Several upgrades will reduce the beam time to only 16 days. A second injection branch with a 28GHz-MS-ECRIS anticipates a factor of 10 in particle intensity. By a new cw rfq-structure all accelerator tanks are suitable for a duty cycle of at least 50% instead of 25% presently. Due to this, thermal power increase of 19 rf-amplifiers eased by higher ion charge states of the ECRIS is necessary. Finally the UNILAC timing system controlling 50Hz pulse-to-pulse operation of up to six beams differing in ion species and energy has to be modified considering beam diagnostics electronics and pulsable magnets. The front end comprising ECRIS, rfq- and IH-structure is cw suitable and will serve as injector for a new future sc-cw-linac.
GSI, Darmstadt
NSCL, East Lansing, Michigan
IAP, Frankfurt am Main
Heavy, highly-charged ions (HCI) with only one or few electrons are interesting systems for precision experiments as for instance tests of the theory of quantum electrodynamics (QED). To achieve high precision, kinetic energy and spatial position of the ions have to be well controlled. This is in contradiction to the production process that employs stripping of electrons at high energies by sending relativistic highly-charged ions with still many electrons through matter. In order to match the production at 400 MeV/u with the requirements of the experiments - stored and cooled HCI at low energy - the linear decelerator facility HITRAP has been built at the experimental storage ring (ESR) at GSI in Darmstadt. The ions are first decelerated in the ESR from 400 to 4 MeV/u, cooled and extracted. The ion beam phase spaces are then matched to an IH-structure, decelerated from 4 to 0.5 MeV/u before a 4-rod RFQ reduces the energy to 6 keV/u. Finally, the HCI are cooled in a Penning trap to 4 K. Extensive ion optical calculations were performed and in recent tests up to one million highly-charged ions have been decelerated from 400 MeV/u to 0.5 MeV/u.
IAP, Frankfurt am Main
Abstract A short RFQ prototype was built for tests of high power RFQ structures. We will study thermal effects and determine critical points of the design. HF-Simulations with CST Microwave Studio and measurements were done. The RF-Tests with continues power of 20 kW/m were finished successfully. Simulations of thermal effects with ALGOR are on focus now. First results and the status of the project will be presented.
IAP, Frankfurt am Main
NTG, Gelnhausen
The IH-type RFQ for the MAFF project at the LMU in Munich was operated at a beam test stand at the IAP in Frankfurt. It is the second IH-RFQ after the HIS at GSI and it has been designed to accelerate rare isotope beams (RIBs) with mass to charge ratios A/q up to 6.3 from 3 keV/u to 300 keV/u at an operating frequency of 101.28 MHz with an electrode voltage of 60 kV. Experimental results such as shunt impedance, energy spectrum and transmission will be presented.
IAP, Frankfurt am Main
GSI, Darmstadt
A new CW-RFQ has been built for the upgrade of the HLI (High Charge State Injector) of GSI for operating with a 28GHz-ECR-Ion source and simultaneous increase of the beam duty cycle from 25 % now to 100 %. The new HLI 4-rod RFQ will accelerate charged ions from 4 keV/u to 300 keV/u for the injection into the IH-structure. High beam transmission, a small energy spread and small transverse emittance growth and good input matching are design goals. Properties of this CW-RFQ, status of project and first measurements will be presented.
IMP, Lanzhou
IAP, Frankfurt am Main
BNL, Upton, Long Island, New York
A compact RFQ for carbon ion beam from a Laser-ion souce is being tested in IMP, Lanzhou. It is the first example of LINAC structures for IMP. Testing schemes and first results are presented.
IMP, Lanzhou
IAP, Frankfurt am Main
BNL, Upton, Long Island, New York
A RFQ has been designed and built for research of direct plasma injection scheme (DPIS), which can provide high current and highly charged beams. Because of the strong space charge forces of beam from laser ion source, the beam dynamics design of the RFQ was carried out with a new code LINACSrfq which can treat space charge effectively due to equipartitioning design strategy. Another feature of the RFQ is its high energy gain in two-meter long which will be described in detail. Construction of the RFQ cavity and the 100MHz/250kW amplifier has been completed and ready for test. A laser ion source is being tested. The assembling of the whole system including the ion source, the RFQ, the beam analyzing and diagnostic system is being done. Preliminary test results will be presented.
IAP, Frankfurt am Main
For the development of high energy and high duty cycle RFQs accurate particle dynamic simulation tools are important for optimizing designs, especially in high current applications. To describe the external fields in RFQs as well as the internal space charge fields with image effect, the Poisson equation has to be solved taking the boundary conditions into account. In PteqHI a multigrid Poisson solver is used to solve the Poisson equation. This method will be described and compared to analytic solutions for the Two-term-potential to verify the answer of the Poisson solver.
BNL, Upton, Long Island, New York
Kyushu University, Hakozaki
IAP, Frankfurt am Main
Department of Energy Sciences, Tokyo Institute of Technology, Yokohama
The EBIS based preinjector for the RHIC is now being commissioned. During the step-wise commissioning of the preinjector from January 2009 to June 2010, the RFQ was commissioned first using Test EBIS in January 2009 and then moved to its final location and commissioned again with RHIC EBIS in March 2010. The RFQ accelerates ions from 17 keV/u to 300 keV/u and operates at 100.625 MHz. The RFQ is followed by a short (81 cm) Medium Energy Beam Transport (MEBT), which consists of four quadrupoles and one buncher cavity. Temporary diagnostics for this commissioning included an emittance probe, TOF system, fast Faraday cup, and beam current measurement units. This contribution will report results of RFQ and MEBT commissioning with helium and gold beams.
BNL, Upton, Long Island, New York
Kyushu University, Hakozaki
IAP, Frankfurt am Main
This talk will present commissioning of a new heavy ion pre-injector at Brookhaven National Laboratory. This preinjector uses an Electron Beam Ion Source (EBIS), and an RFQ and IH Linac, both operating at 100.625 MHz, to produce 2 MeV/u ions of any species for use, after further acceleration, at the Relativistic Heavy Ion Collider, and the NASA Space Radiation Laboratory. Among the increased capabilities provided by this preinjector are the ability to produce ions of any species, and the ability to switch between multiple species in 1 second, to simultaneously meet the needs of both physics programs.