• M.L. Neubauer, K.B. Beard, R. Sah
  Muons, Inc, Batavia
• C. Hernandez-Garcia, G. Neil
  JLAB, Newport News, Virginia

Funding: Supported in part by USDOE Contract No. DE-AC05-84-ER-40150.

Many user facilities such as synchrotron light sources and free electron lasers require accelerating structures that support electric fields of 10-100 MV/m, especially at the start of the accelerator chain where ceramic insulators are used for very high gradient DC guns. These insulators are difficult to manufacture, require long commissioning times, and have poor reliability, in part because energetic electrons bury themselves in the ceramic, creating a buildup of charge and causing eventual puncture. A novel ceramic manufacturing process is proposed. It will incorporate bulk resistivity in the region where it is needed to bleed off accumulated charge caused by highly energetic electrons. This process will be optimized to provide an appropriate gradient in bulk resistivity from the vacuum side to the air side of the HV standoff ceramic cylinder. A computer model will be used to determine the optimum cylinder dimensions and required resistivity gradient for an example RF gun application. A ceramic material example with resistivity gradient appropriate for use as a DC gun insulator will be fabricated by glazing using doping compounds and tested.

• S.L. Smith, R. Bate, C.D. Beard, M.A. Bowler, R.K. Buckley, S.R. Buckley, J.A. Clarke, P.A. Corlett, M. Dufau, D.J. Dunning, B.D. Fell, P. Goudket, A.R. Goulden, S.A. Griffiths, J.D. Herbert, C. Hill, F. Jackson, S.P. Jamison, J.K. Jones, L.B. Jones, A. Kalinin, N. Marks, P.A. McIntosh, J.W. McKenzie, K.J. Middleman, B.L. Militsyn, A.J. Moss, B.D. Muratori, J.F. Orrett, S.M. Pattalwar, P.J. Phillips, M.W. Poole, Y.M. Saveliev, D.J. Scott, B.J.A. Shepherd, R.J. Smith, N. Thompson, B. Todd, T.M. Weston, A.E. Wheelhouse, P.H. Williams
  STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
• J.R. Alexander, P. Atkinson, N. Bliss, I. Burrows, G. Cox, P.A.D. Dickenson, A. Gallagher, K.D. Gleave, J.P. Hindley, B.G. Martlew, I.D. Mullacrane, A. Oates, P.D. Quinn, D.G. Stokes, J. Strachan, P.J. Warburton, C.J. White
  STFC/DL, Daresbury, Warrington, Cheshire
• W.R. Flavell, E.A. Seddon
  UMAN, Manchester
• F.G. Gabriel
  FZD, Dresden
• C. Gerth
  DESY, Hamburg
• F.E. Hannon, C. Hernandez-Garcia, K. Jordan, G. Neil
  JLAB, Newport News, Virginia
• K. Harada
  KEK, Ibaraki
• P. Harrison, D.J. Holder, G.M. Holder, P. Weightman
  The University of Liverpool, Liverpool
• S.F. Hill, G. Priebe, R.V. Rotheroe, M. Surman
  STFC/DL/SRD, Daresbury, Warrington, Cheshire
• G.J. Hirst, P.G. Huggard
  STFC/RAL, Chilton, Didcot, Oxon
• P. vom Stein
  ACCEL, Bergisch Gladbach

ALICE (Accelerators and Lasers in Combined Experiments) is a 35 MeV energy recovery linac based light source. ALICE is being developed as an experimental test-bed for a broad suite of science and technology activities that make use of electron acceleration and ultra-short pulse laser techniques. This paper reports the progress made in accelerator commissioning and includes the results of measurement made on the commissioning beam. The steps taken to prepare the beam for short pulse operation as a driver for a Compton Back Scattered source and in preparation for the commissioning of the free electron laser are reported.