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Niobium Quarter-Wave Resonator Development for The Rare Isotope Accelerator

W. Hartung·J. Bierwagen·S. Bricker·J. Colthorp·C. Compton·T. Grimm·S. Hitchcock·F. Marti·L. Saxton·R. C. York·A. Facco·V. Zviagintsev
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Abstract

Two superconducting quarter-wave resonator (QWR) prototypes have been fabricated and tested. They operate at 80.5 MHz and 161 MHz and are optimised for beta = 0.085 and beta = 0.16, respectively. The prototypes are simplified versions without integrated helium vessels. In the first RF tests, the beta = 0.085 QWR reached a peak surface electric field (Ep) in excess of 30 MV/m, with an intrinsic quality factor (Q0) in excess of 1E9 at the design field of Ep = 20 MV/m. The beta = 0.16 QWR reached Ep = 20 MV/m with Q0 = 2.5E9. It is suspected that the performance of the latter cavity can be improved via better cooling of the Nb tuning plate and a better RF contact between the plate and the outer conductor.

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W. Hartung, J. Bierwagen, S. Bricker, J. Colthorp, C. Compton, T. Grimm, S. Hitchcock, F. Marti, L. Saxton, R. C. York, A. Facco, V. Zviagintsev. 2004-12-04. Niobium Quarter-Wave Resonator Development for The Rare Isotope Accelerator. https://arxiv.org/abs/physics/0412031

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