| Paper | Title | Page |
|---|---|---|
| THPF008 | U28+ Intensity Record Applying a H2-Gas Stripper Cell | 3693 |
|
||
| Meeting the FAIR science requirements higher beam intensity has to be achieved in the present GSI-accelerator complex. An advanced upgrade program for the UNILAC aimed to meet the FAIR requirements. Stripping is a key technology for all heavy ion accelerators. For this an extensive research and development program was carried out to optimize for high brilliance heavy ion operation. After upgrade of the supersonic N2-gas jet, implementation of high current foil stripping and preliminary investigation of H2 gas jet operation, recently a newly developed H2 gas cell uses a pulsed gas regime synchronized with arrival of the beam pulse. An obviously enhanced stripper gas density as well as a simultaneously reduced gas load for the pumping system result in an increased stripping efficiency, while the beam emittance remains the same. A new record intensity (7.8 emA) for U28+ beams at 1.4 MeV/u has been achieved applying the pulsed high density H2 stripper target, while the MeVVa ion source with a newly developed extraction system delivered a high intensity U4+ beam. The experimental results will be presented in detail. | ||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF008 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| THPF013 | UNILAC Proton Injector Operation for FAIR | 3709 |
|
||
| The pbar physics program at the Facility for Antiproton and Ion Research (FAIR) requires a high number of cooled pbars per hour. The FAIR proton injector with coupled CH-cavities will provide for a high intensity (35 mA) pulsed 70 MeV proton beam at a repetition rate of 4 Hz. The recent heavy ion UNIversal Linear Accelerator (UNILAC) at GSI is able to deliver proton as well as heavy ion beams for injection into the FAIR-synchrotrons. Recently GSI UNILAC could provide for a two orders of magnitude higher proton beam current in routine operation. A hydrocarbon beam (CH3) from the MUCIS ion source was accelerated inside High Current Injector and cracked in a supersonic nitrogen gas jet into stripped protons and carbon ions. A new proton beam intensities record (3 mA) could be achieved during machine experiments in October 2014. Potentially up to 25% of the FAIR proton beam performance is achievable at a maximum UNILAC beam energy of 20 MeV and a repetition rate of 4 Hz. The UNILAC can be used as a high performance proton injector for initial FAIR-commissioning and as a redundant option for the first FAIR-experiments. | ||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF013 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| THPF020 | Upgrade of the HSI-RFQ at GSI to Fulfill the FAIR Requirements | 3727 |
|
||
| In Darmstadt/Germany the existing accelerator facility GSI is expanding to one of the biggest joint research projects worldwide: FAIR, a new antiproton and ion research facility with so far unmatched intensities and quality. The existing accelerators will be used as pre-accelerators and therefor need to be upgraded. In a first step the 36 MHz-HSI-RFQ for high current beams will get new electrodes to fulfill the FAIR requirements. First simulation results for capacity and multipole momentums will be presented. | ||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF020 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| THPF021 | Structural, Mechanical and RF Measurements on the Superconducting 217 MHz CH Cavity for the CW Demonstrator at GSI | 3730 |
|
||
|
Funding: Work supported by HIM, GSI, BMBF Contr. No. 05P12RFRBL Together with the new horizontal cryomodule and two superconducting (sc) 9.5 T solenoids the sc 217 MHz Crossbar-H-mode (CH) cavity represents the continuous wave (cw) demonstrator and brings sc rf technology to GSI. A reliable operability of the sc CH cavity is one major goal of the demonstrator project. Furthermore, the successful beam operation of the demonstrator will be a milestone on the way to a new sc cw linac at GSI for a competitive production of Super Heavy Elements (SHE) in the future. The production of the cryomodule and the solenoids is almost finished while the cavity has been completed except for the helium vessel. In this paper structural mechanical as well as related rf measurements on the sc 217 MHz CH cavity are presented. |
||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF021 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| THPF025 | Beam Dynamics for the SC CW Heavy Ion LINAC at GSI | 3742 |
|
||
|
Funding: Work supported by BMBF contr. No. 05P12RFRBL For future experiments with heavy ions near the coulomb barrier within the SHE (super-heavy elements) research project a multi-stage R&D program of GSI, HIM and IAP is currently in progress*. It aims at developing a superconducting (sc) continuous wave (cw) LINAC with multiple CH cavities as key components downstream the High Charge Injector (HLI) at GSI. The beam dynamics concept is based on EQUUS (equidistant multigap structure) constant-beta cavities. Advantages of its periodicity are a high simulation accuracy, easy manufacturing and tuning with minimized costs as well as a straightforward energy variation. The next milestone will be a full performance beam test of the first LINAC section, comprising two solenoids and a 15-gap CH cavity inside a cryostat (Demonstrator). *W. Barth et al., ‘‘Further R&D for a new Superconducting cw Heavy Ion LINAC@GSI'', THPME004, IPAC'14, Dresden, Germany (2014) |
||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF025 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |
| THPF035 | Stripping of High Intensity Heavy-Ion Beams in a Pulsed Gas Stripper Device at 1.4 MeV/u | 3773 |
|
||
| As part of an injector system for FAIR, the GSI UNILAC has to meet high demands in terms of beam brilliance at a low duty factor. To accomplish this goal an extensive upgrade program has started. To increase the beam intensity behind the UNILAC, it is aimed to increase the efficiency of the 1.4 MeV/u gas stripper. A modification of the stripper setup was developed to replace the N2-jet with a pulsed gas injection, synchronized with the transit of the beam pulse. The pulsed gas injection lowers the gas load for the differential pumping system, rendering possible the use of other promising gas targets. In recent measurements the performance of the modified setup was tested using an 238U-beam with various stripper media, including H2, He, and N2. The data provide a systematic basis for an improved understanding of slow heavy ions passing through gaseous media. The stripping performance of the current N2-jet was excelled by using H2 at increased gas densities, enabled by the new pulsed gas cell. | ||
| DOI • | reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF035 | |
| Export • | reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml) | |