A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z    

Kang, Y.W.

Paper Title Page
TPPT039 Installation and Testing for Commissioning of Normal Conducting RF Linac Segment in the SNS 2571
 
  • Y.W. Kang, A.V. Aleksandrov, D.E. Anderson, M.M. Champion, M. Champion, M.T. Crofford, C. Deibele, G.W. Dodson, R.E. Fuja, P.E. Gibson, P.A. Gurd, T.W. Hardek, G.A. Johnson, P. Ladd, H. Ma, M.P. McCarthy, M.F. Piller, J.Y. Tang, A.V. Vassioutchenko, D.C. Williams
    ORNL, Oak Ridge, Tennessee
  • J.A. Billen, J.T. Bradley, D. Rees, W. Roybal, J. Stovall, K.A. Young, L.M. Young
    LANL, Los Alamos, New Mexico
  
  The Spallation Neutron Source (SNS) linac employs both normal conducting and superconducting linac cavities that will inject a 1.0 GeV proton beam into its accumulator ring. The normal conducting segment of this linac accelerates the beam to 185 MeV and employs one RFQ and six DTL cavities powered by seven 2.5 MW, 402.5 MHz klystrons and four CCL modules powered by four 5.0 MW, 805 MHz klystrons. Installation and RF conditioning of the RF equipment for normal conducting linac segment have been completed at ORNL with the support of LANL experts. After conditioning the accelerating structures, the linac has been successfully commissioned with beam. This paper reviews the experience in installation, RF conditioning, and commissioning of the normal conducting linac accelerating structures and RF subsystems. Checkout and operation of the RF systems and structures including conditioning procedure establishment and test results compared to the RF design specifications will be discussed.

SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. SNS is a partnership of six national laboratories: Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Los Alamos, and Oak Ridge.

 
TPPT083 RF Conditioning and Testing of Fundamental Power Couplers for SNS Superconducting Cavity Production 4132
 
  • M. Stirbet, G.K. Davis, M. A. Drury, C. Grenoble, J. Henry, G. Myneni, T. Powers, K. Wilson, M. Wiseman
    Jefferson Lab, Newport News, Virginia
  • I.E. Campisi, Y.W. Kang, D. Stout
    ORNL, Oak Ridge, Tennessee
  
  Funding: This work was supported by U.S. DOE contract DE-AC0500R22725.

The Spallation Neutron Source (SNS) makes use of 33 medium beta (0.61) and 48 high beta (0.81) superconducting cavities. Each cavity is equipped with a fundamental power coupler, which should withstand the full klystron power of 550 kW in full reflection for the duration of an RF pulse of 1.3 msec at 60 Hz repetition rate. Before assembly to a superconducting cavity, the vacuum components of the coupler are submitted to acceptance procedures consisting of preliminary quality assessments, cleaning and clean room assembly, vacuum leak checks and baking under vacuum, followed by conditioning and RF high power testing. Similar acceptance procedures (except clean room assembly and baking) were applied for the airside components of the coupler. All 81 fundamental power couplers for SNS superconducting cavity production have been RF power tested at JLAB Newport News and, beginning in April 2004 at SNS Oak Ridge. This paper gives details of coupler processing and RF high power-assessed performances.

 
WPAT059 High Power RF Test Facility at the SNS 3450
 
  • Y.W. Kang, D.E. Anderson, I.E. Campisi, M. Champion, M.T. Crofford, R.E. Fuja, P.A. Gurd, S. Hasan, K.-U. Kasemir, M.P. McCarthy, D. Stout, J.Y. Tang, A.V. Vassioutchenko, M. Wezensky
    ORNL, Oak Ridge, Tennessee
  • G.K. Davis, M. A. Drury, T. Powers, M. Stirbet
    Jefferson Lab, Newport News, Virginia
  
  RF Test Facility has been completed in the SNS project at ORNL to support test and conditioning operation of RF subsystems and components. The system consists of two transmitters for two klystrons powered by a common high voltage pulsed converter modulator that can provide power to two independent RF systems. The waveguides are configured with WR2100 and WR1150 sizes for presently used frequencies: 402.5 MHz and 805 MHz. Both 402.5 MHz and 805 MHz systems have circulator protected klystrons that can be powered by the modulator capable of delivering 11 MW peak and 1 MW average power. The facility has been equipped with computer control for various RF processing and complete dual frequency operation. More than forty 805 MHz fundamental power couplers for the SNS superconducting linac (SCL) cavitites have been RF conditioned in this facility. The facility provides more than 1000 ft2 floor area for various test setups. The facility also has a shielded cave area that can support high power tests of normal conducting and superconducting accelerating cavities and components.

SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. SNS is a partnership of six national laboratories: Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Los Alamos, and Oak Ridge.

 
WPAT061 Spallation Neutron Source High Power RF Installation and Commissioning Progress 3520
 
  • M.P. McCarthy, D.E. Anderson, R.E. Fuja, P.A. Gurd, T.W. Hardek, Y.W. Kang
    ORNL, Oak Ridge, Tennessee
  • J.T. Bradley, D. Rees, W. Roybal, K.A. Young
    LANL, Los Alamos, New Mexico
  
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy.

The Spallation Neutron Source (SNS) linac will provide a 1 GeV proton beam for injection into the accumulator ring. In the normal conducting (NC) section of this linac, the Radio Frequency Quadupole (RFQ) and six drift tube linac (DTL) tanks are powered by seven 2.5 MW, 402.5 MHz klystrons and the four coupled cavity linac (CCL) cavities are powered by four 5.0 MW, 805 MHz klystrons. Eighty-one 550 kW, 805 MHz klystrons each drive a single cavity in the superconducting (SC) section of the linac. The high power radio frequency (HPRF) equipment was specified and procured by LANL and tested before delivery to ensure a smooth transition from installation to commissioning. Installation of RF equipment to support klystron operation in the 350-meter long klystron gallery started in June 2002. The final klystron was set in place in September 2004. Presently, all RF stations have been installed and high power testing has been completed. This paper reviews the progression of the installation and testing of the HPRF Systems.

 
WPAT085 4.2 K Operation of the SNS Cryomodules 4173
 
  • I.E. Campisi, S. Assadi, F. Casagrande, M. Champion, C. Chu, S.M. Cousineau, M.T. Crofford, C. Deibele, J. Galambos, P.A. Gurd, D.R. Hatfield, M.P. Howell, D.-O. Jeon, Y.W. Kang, K.-U. Kasemir, Z. Kursun, H. Ma, M.F. Piller, D. Stout, W.H. Strong, A.V. Vassioutchenko, Y. Zhang
    ORNL, Oak Ridge, Tennessee
  
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy. SNS is a partnership of six national laboratories: Argonne, Brookhaven, Jefferson, Lawrence Berkeley, Los Alamos and Oak Ridge.

The Spallation Neutron Source being built at the Oak Ridge National Laboratory employs eighty one 805 MHz superconducting cavities operated at 2.1 K for the H- beam to gain energy in the main linac from 187 MeV to about 1 GeV. The superconducting cavities and cryomodules with two different values of beta .61 and .81 have been designed and constructed at Jefferson Lab for operation at 2.1 K with unloaded Q’s in excess of 5x109. To gain experience in testing cryomodules in the SNS tunnel before the final commissioning of the 2.1 K Central Helium Liquefier, integration tests were conducted on a medium beta (.61) cryomodule at 4.2 K. This is the first time that a superconducting cavity system specifically designed for 2.1 K operation has been extensively tested at 4.2 K without superfluid helium. Even at 4.2 K it was possible to test all of the functional properties of the cryomodule and of the cavities. In particular, at a nominal BCS Qo˜7x108, simultaneous pulse operation of all three cavities in the cryomodule was achieved at accelerating gradients in excess of 12 MV/m. These conditions were maintained for several hours at a repetition rate of 30 pps. Details of the tests will be presented and discussed.