• R.E. Laxdal, C.D. Beard, R.J. Dawson, K. Fong, A. Grassellino, M.P. Laverty, D. Longuevergne, M. Marchetto, A.K. Mitra, T.C. Ries, I. Sekachev, Q. Zheng, V. Zvyagintsev
  TRIUMF, Vancouver

The ISAC-II Phase II expansion includes the addition of 20 new quarter wave resonators in three cryomodules to double the energy gain of the ISAC-II superconducting linac. The rf cavities are produced in Canada. The talk will concentrate on the beam commissioning (scheduled for March 2010) and early operating experience.

• D. Longuevergne
  UBC & TRIUMF, Vancouver, British Columbia
• C.D. Beard, A. Grassellino, P. Kolb, R.E. Laxdal, V. Zvyagintsev
  TRIUMF, Vancouver

The upgrade (Phase II) of the ISAC-II superconducting linac has been completed this spring and has been commissioned. Two spare 141 MHz Quarter-Wave Resonators made of bulk Niobium are available at TRIUMF to lead more specific studies on surface resistance. This opportunity has also been taken to optimize the surface treatment to improve the accelerating field gradient at the operating power level. The aim of the study presented here is to link together several surface treatments (etching depth, 120C baking) and test conditions (Q-disease, 4.2 K and 2K tests) and sequence them in an appropriate order to understand more deeply their dependencies.

• M.P. Laverty, K. Fong, R.E. Laxdal, Q. Zheng
  TRIUMF, Vancouver
• G. Dennison
  UBC & TRIUMF, Vancouver, British Columbia

The rf control system for the twenty 141 MHz TRIUMF quarter wave superconducting cavities is a hybrid analogue/digital design. It is based in part on an earlier design developed for the 106MHz 1/4 wave superconducting cavities of the ISACII linac. This design has undergone several iterations in the course of its development. In the current version, a value-engineering approach was used to reduce the cost and simplify the hardware. The result is a single C-size VXI module that incorporates all the required low-level rf functions - amplitude/phase control, tuning control, and control of the rf coupler. It accomplishes these functions at a substantially lower cost than the previous two-module solution. It also includes support for field upgrade of the DSP/PLD hardware and firmware. Some early test results of the system operating in the linac are outlined, and conclusions are summarized.

• V. Naik, A. Bandyopadhyay, A. Chakrabarti, S. Dechoudhury, M. Mondal
  DAE/VECC, Calcutta
• F. Ames, R.A. Baartman, C.D. Beard, Y.-C. Chao, R.J. Dawson, P. Kolb, S.R. Koscielniak, R.E. Laxdal, M. Marchetto, L. Merminga, A.K. Mitra, T.C. Ries, I. Sekachev, V.A. Verzilov, F. Yan
  TRIUMF, Vancouver
• D. Longuevergne
  UBC & TRIUMF, Vancouver, British Columbia

TRIUMF (Canada) and VECC (India) are both planning to use the photo-fission route for producing neutron-rich radioactive ion beams in their respective RIB programmes. With this common goal the two institutes have entered into a collaboration to jointly design and develop a superconducting 1.3GHz 50MeV, 10 mA, CW electron linac which will be used as the fission driver. The first phase of the e-Linac collaboration aims at the development, production and full technical and beam test of a 10MeV injector cryo module (ICM) which forms the front-end of the final linac. The design and technical development of the ICM will be presented.

• Y. Ma
  CIAE, Beijing
• A. Facco, F. Scarpa
  INFN/LNL, Legnaro (PD)

The low-beta section of the EURISOL driver linac is based on 176 MHz superconducting half-wave resonators (HWR) with beta=0.09 and 0.16. These cavities are an evolution of the 352 MHz ones, previously developed in the same framework, having similar dimensions and components except for their length and rf frequency. They are characterized by a double wall, all niobium structure with light weight, good mechanical stability and a side tuner cooled by thermal conduction. The new 176 MHz Half-wave cavities design includes a removable tuner, which allows to improve tuning range, mechanical stability and accessibility to the cavity interior. A beta=0.13 cavity, which could be suitable for linacs like the SARAF one, was also designed with the same concepts. Design characteristics and expected performance will be presented and discussed.

• R.E. Laxdal, C.D. Beard, A. Grassellino, P. Kolb, S.R. Koscielniak, V. Zvyagintsev
  TRIUMF, Vancouver
• D. Longuevergne
  UBC & TRIUMF, Vancouver, British Columbia
• R.S. Orr, W. Trischuk
  University of Toronto, Toronto, Ontario

TRIUMF has embarked on a 1.3GHz development program to support the construction of a 50MeV 10mA e-Linac for the production of radioactive ion beams through photo-fission. Two single cell bulk niobium cavities have been produced in Canadian Industry. A seven-cell cavity in copper is being fabricated both as a manufacturing model and to test higher order mode calculations. Electro-magnetic and mechanical models of a multi-cell cavity are being done to optimize the final design for high intensity acceleration. The 1.3GHz cavity development program will be presented.