| Paper | Title | Page |
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| TUP039 | Two-Charge-State Injector for a High Power Heavy-Ion Linac* | 336 |
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A permanent magnet (PM) ECR ion source and following low energy beam transport (LEBT) system with the capability to deliver two-charge-state heavy-ion beams (2Q-LEBT) for high-power linacs is being prototyped at Argonne. The injector consists of the PM ECR ion source, transport line with beam diagnostics including emittance measurements and a multi-harmonic buncher. Recently the ECR ion source has been installed on a high voltage platform to increase the accelerating voltage up to the design value of 100 kV. The unique feature of the 2Q-LEBT layout is that the charge separation is performed off of the platform after acceleration of a multi-component ion beam. This layout allows us to analyze and recombine two-charge-state beams using an achromatic bending system. Improvements of the PM ECR performance and beam optics studies based on measurements of various heavy-ion beams will be discussed in this paper.
*This work was supported by the U. S. Department of Energy, Office of Nuclear Physics, under Contract No. W-31-109-ENG-38 |
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| THP079 | High-Power Test of a 57-MHz CW RFQ | 767 |
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High power heavy-ion drivers require a CW low-frequency RFQ for initial acceleration. The technique of high-temperature furnace brazed OFE copper cavities has proven to be very reliable for the production of high-quality CW accelerating structures. By appropriate choice of the resonant structure for the RIA driver RFQ we have achieved moderate transverse dimensions of the cavity and high quality accelerating-focusing fields required for simultaneous acceleration of multiple charge state ion beams. In our application the RFQ must provide stable operation over a wide range of RF power levels. To demonstrate the technology and high-power operation we have built an engineering prototype of one-segment of the 57-MHz RFQ structure [1]. The RFQ is designed as a 100% OFE copper structure and fabricated with a two-step furnace brazing process. The brazing process was successful and the cavity was shown to be vacuum tight. The errors in the tip-to-tip distances of the vanes average less than 50 microns. The RF measurements show excellent electrical properties of the resonator with a measured unloaded Q equal to 95% of the simulated value. Currently high-power tests are being performed.
*J. W. Rathke et al., Preliminary Engineering Design of A 57.5 MHz CW RFQ for the RIA Driver LINAC. Proc. of the LINAC-2002, p. 467. |