JACoW is a publisher in Geneva, Switzerland that publishes the proceedings of accelerator conferences held around the world by an international collaboration of editors.
TY - CONF AU - McGee, K.E. AU - Elliott, K. AU - Eremeev, G.V. AU - Furuta, F. AU - Ganshyn, A. AU - Guilfoyle, B.M. AU - Hartung, W. AU - Kelly, M.P. AU - Kim, S.H. AU - Martinello, M. AU - Melnychuk, O.S. AU - Netepenko, A.V. AU - Ostroumov, P.N. AU - Popielarski, J.T. AU - Popielarski, L. AU - Reid, T. AU - Taylor, A. AU - Xu, T. ED - McIntosh, Peter ED - Burt, Graeme ED - Apsimon, Robert ED - Schaa, Volker R.W. TI - Developments Towards FRIB Upgrade to 400 MeV/u for Heaviest Uranium Ions J2 - Proc. of LINAC2022, Liverpool, UK, 28 August-02 September 2022 CY - Liverpool, UK T2 - International Linear Accelerator Conference T3 - 31 LA - english AB - High-Q₀ medium-velocity (beta opt = 0.6) 5-cell elliptical cavities for superconducting linacs are critical technology for advancing current and future projects such as the Proton Improvement Plan II linac and the proposed energy upgrade of Michigan State University’s Facility For Rare Isotope Beams linac, FRIB400. Previous work established the validity of the novel geometry of the FRIB400 prototype 644 MHz 5-cell elliptical β = 0.65 cavities for future high Q₀ development. In collaboration with FNAL, two leading-edge high-Q₀ recipes, N-doping and Mid-T baking, were tested in the 5-cell format. 2/0 N-doping + cold electropolishing was successful at achieving FRIB400 and PIP-II Q₀ requirements, achieving an unprecedented 3.8 x 10¹⁰ at 17.5 MV/m, satisfying the FRIB400 Q₀ requirements by 1.75 times in a low-gauss environment. Mid-T baking exceeded FRIB400 Q₀ requirements by 1.4 times, and benefitted from decreased residual resistance compared to the N-doped cavity test. Systematic ultrasonic thickness measurements in single-cell revealed bulk (150 microns) EP with the modified EP tool is consistent across the inner surfaces of the cavity walls. PB - JACoW Publishing CP - Geneva, Switzerland SP - 653 EP - 656 KW - cavity KW - background KW - cryomodule KW - ECR KW - linac DA - 2022/09 PY - 2022 SN - 2226-0366 SN - 978-3-95450-215-8 DO - doi:10.18429/JACoW-LINAC2022-TH1AA02 UR - https://jacow.org/linac2022/papers/th1aa02.pdf ER -