Author: Padamsee, H.
Paper Title Page
MOP086 Integration, Commissioning and Cryogenics Performance of the ERL Cryomodule Installed on ALICE-ERL Facility at STFC Daresbury Laboratory, UK 349
 
  • S.M. Pattalwar, R.K. Buckley, P.A. Corlett, P. Goudket, A.R. Goulden, A.J. May, P.A. McIntosh, A.E. Wheelhouse
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • S.A. Belomestnykh
    BNL, Upton, Long Island, New York, USA
  • A. Büchner, F.G. Gabriel, P. Michel
    HZDR, Dresden, Germany
  • E.P. Chojnacki, J.V. Conway, R.G. Eichhorn, G.H. Hoffstaetter, M. Liepe, H. Padamsee, P. Quigley, J. Sears, V.D. Shemelin
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • M.A. Cordwell, T.J. Jones, L. Ma, A.J. Moss, J. Strachan
    STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
  • J.N. Corlett, D. Li, S.M. Lidia
    LBNL, Berkeley, California, USA
  • T. Kimura
    Stanford University, Stanford, California, USA
  • R.E. Laxdal
    TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
  • J.K. Sekutowicz
    DESY, Hamburg, Germany
  • T.J. Smith
    SLAC, Menlo Park, California, USA
  
  On successful assembly and preliminary testing of an optimised SRF cryomodule for application on ERL accelerators, which is being developed through an international collaboration the cryomodule has been installed on the 35 MeV ALICE (Accelerators and Lasers in Combined Experiments) Energy Recovery Linac (ERL) facility at STFC Daresbury Laboratory. Existing cryogenic infrastructure has a capacity to deliver approximately 120 W cooling power at 2 K, but the HOM (Higher Order Mode) absorbers, the thermal intercepts for the high power RF couplers and the radiation shield in the cryomodule are designed to be cooled (to 5 K and 80 K) with gaseous helium instead of liquid nitrogen. As a result the cryogenic infrastructure for ALICE had to be modified to meet these additional requirements. In this paper we describe our experience with the process of integration and the cryogenic commissioning, and present some initial results.  
 
TUP105 Investigation of the Surface Resistivity of SRF Cavities via the Heat and Srimp Program as Well as the Multi-Cell T-Map System 724
 
  • G.M. Ge, D. Gonnella, G.H. Hoffstaetter, M. Liepe, H. Padamsee
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • F. Furuta
    Cornell University, Ithaca, New York, USA
  
  A high-sensitive temperature mapping system for multi-cell SRF cavities has been constructed at Cornell University. The resolution of the system is 1mK. Hence it’s able to detect small temperature increases when cavities reach at low accelerating gradients e.g. 3MV/m. The surface resistivity of superconductor under radio-frequency electromagnetic field can be calculated from the temperature increases. In this contribution, the surface resistance map of multi-cell SRF cavities is shown. The temperature mapping result is possible to establish a relationship between the surface resistivity and the magnetic field as well. Unlike the RF method which is average value of the surface resistance, the T-map results give local surface resistivity versus magnetic field. BCS theory assumes the surface resistivity is independent to the magnetic field. The T-map results, however, suggest that the surface resistance at high-loss region is field dependent and caused Q-slope.