• M.P. Kelly, J.D. Fuerst, S.M. Gerbick, M. Kedzie, P.N. Ostroumov, K.W. Shepard, G.P. Zinkann
  ANL, Argonne

A set of six new 109 MHz β=0.15 superconducting quarter-wave resonators (QWR) has been built at ANL as part of an upgrade to the ATLAS superconducting heavy-ion linac. The final cavity string assembly will also use many of the techniques needed for the next generation of large high-performance ion linacs such as the U.S. Department of Energy's FRIB project. Single-cavity cold tests at T=4.5 K have been performed for three cavities with moveable coupler, rf pickup, and VCX fast tuner as required for the full 6-meter cryomodule assembly. The average maximum accelerating gradient of 4 cavities (3 new + 1 prototype), is EACC=11.2 MV/m (BPEAK=65 mT). Clean cavity string assembly techniques, required here and for most future SRF ion linacs, are fairly well developed. Details on cavity performance including high-field cw operation, microphonics and fast tuning are presented.

• M.P. Kelly, S.M. Gerbick
  ANL, Argonne
• D.R. Olis, A.M. Rowe
  Fermilab, Batavia

New SRF cavity processing systems at ANL, including those for electropolishing (EP), high-pressure water rinsing (HPR), and single-cavity clean room assembly have been developed and operated at ANL for use with cavities for a range of electron and ion linac applications. Jointly with FNAL, systems for 1.3 GHz single- and multi-cell elliptical cavities for the linear collider effort have been developed. New systems for use with low-beta TEM-class cavities have also been built and used to process a set of new quarter-wave resonators as part of an upgrade to the ATLAS heavy-ion accelerator at ANL. All of the new hardware is located in a 200 m2 joint ANL/FNAL Superconducting Cavity Surface Process Facility (SCSPF) consisting of two separate chemical processing rooms, a clean anteroom, and a pair of class 10 and 100 clean rooms for HPR and clean assembly. Results of first cold tests for elliptical and TEM-class cavities processed in these facilities are presented.

• G. Apollinari, I.G. Gonin, T.N. Khabiboulline, G. Lanfranco, A. Mukherjee, J.P. Ozelis, L. Ristori, G.V. Romanov, D.A. Sergatskov, R.L. Wagner, R.C. Webber
  Fermilab, Batavia
• J.D. Fuerst, M.P. Kelly, K.W. Shepard
  ANL, Argonne

The High Intensity Neutrino Source (HINS) project represents the current effort at Fermilab to develop 60 MeV Proton/H^- Linac as a front end for possible use in the Project X. Eighteen superconducting β=0.21 single spoke resonators (SSR), operating at 325 MHz, comprise the first stage of the HINS cold section. Two SSR cavities have now been fabricated in industry under this project and undergone surface treatment that is described here. We report the results of high gradient tests of the first SSR in the Vertical Test System (VTS). The cavity successfully achieved accelerating gradient of 13.5 MV/m; higher than the design operating gradient of 10 MV/m. The history of multipacting and conditioning during the VTS tests will be discussed. Experimental measurements of the cavity mechanical and vibration properties including Lorenz force detuning and measurements of X-rays resulting from field emission are also presented.