Author: Power, J.G.
Paper Title Page
MOPFI076 Electron Emission Studies in the New High-charge Cs2Te Photoinjector at Argonne National Laboratory 455
 
  • E.E. Wisniewski, M.E. Conde, W. Gai, C.-J. Jing, W. Liu, J.G. Power
    ANL, Argonne, USA
  • L.K. Spentzouris, Z.M. Yusof
    Illinois Institute of Technology, Chicago, Illinois, USA
 
  Funding: This work was funded by the U.S. Dept. of Energy Office of Science under contract number DE-AC02-06CH11357.
A new L-band 1.3 GHz 1.5 cell gun for the new 75 MeV drive beam is being commissioned and will soon be operating at the Argonne Wakefield Accelerator (AWA) facility as part of the facility upgrade (see M. E. Conde, this proceedings.) The photoinjector is high-field (peak accelerating field > 80MV/m) and has a large \mathrm{Cs}2\mathrm{Te} photocathode (diameter > 30 mm) fabricated in-house. The photoinjector generates high-charge, short pulse, single bunches (Q > 100 nC) or bunch-trains (Q ≈ 1000 nC) for wakefield experiments. Field emission from the \mathrm{Cs}2\mathrm{Te} cathode is to be measured during RF conditioning and benchmarked against measurements from a copper cathode. Quantum efficiency (QE) will be measured in single and multi-bunch modes. Preliminary results are presented.
 
 
TUOCB101 Argonne Wakefield Accelerator (AWA): A Facility for the Development of High Gradient Accelerating Structures and Wakefield Measurements 1111
 
  • M.E. Conde, S.P. Antipov, D.S. Doran, W. Gai, C.-J. Jing, R. Konecny, W. Liu, J.G. Power, E.E. Wisniewski, Z.M. Yusof
    ANL, Argonne, USA
  • S.P. Antipov, C.-J. Jing, R. Konecny
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • E.E. Wisniewski, Z.M. Yusof
    Illinois Institute of Technology, Chicago, Illinois, USA
 
  Funding: Work supported by the U.S. Department of Energy under contract No. DE-AC02-06CH11357.
The recently upgraded AWA facility is being commissioned. Operation of the new L-Band RF gun with a Cesium Telluride photocathode will generate long electron bunch trains, with high charge per bunch (up to 100 nC). The six new linac tanks will boost the beam energy to 75 MeV, making it an extremely well suited drive beam to excite wakefields in structures. One of the main goals of the facility is to generate RF pulses with GW power levels, corresponding to accelerating gradients of hundreds of MV/m and energy gains on the order of 100 MeV per structure. A key aspect of the studies and experiments carried out at the AWA facility is the use of relatively short RF pulses (15 – 25 ns), which is believed to mitigate the risk of breakdown and structure damage.
 
slides icon Slides TUOCB101 [3.416 MB]  
 
TUPEA087 Experiment on Multipactor Suppression in Dielectric-loaded Accelerating Structures with a Solenoid Field 1319
 
  • C.-J. Jing, S.P. Antipov, A. Kanareykin, P. Schoessow
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • C. Chang, L. Ge, L. Xiao
    SLAC, Menlo Park, California, USA
  • M.E. Conde, W. Gai, R. Konecny, J.G. Power
    ANL, Argonne, USA
  • S.H. Gold
    NRL, Washington, DC, USA
 
  Funding: US DoE SBIR Phase I project under contract #DE-SC0007629
Efforts by numerous institutions have been ongoing over the past decade to develop a Dielectric-Loaded Accelerating (DLA) structure capable of supporting high gradient acceleration when driven by an external rf source. Multipactor is the major issue limiting the gradient that was revealed in earlier experiments. A theoretical model predicts that the strength of solenoid field within an optimal range applied to DLA structures may completely block the multipactor. To demonstrate this approach, two DLA test structures have been built and the first high power test will be conducted in December 2012. The results will be reported.
 
 
TUPEA088 Argonne Flexible Linear Collider 1322
 
  • C.-J. Jing, S.P. Antipov, A. Kanareykin, P. Schoessow
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • M.E. Conde, W. Gai, J.G. Power
    ANL, Argonne, USA
 
  We propose a linear collider based on a short rf pulse (~22ns flat top), high gradient (~120MV/m loaded gradient), high frequency (26GHz) two beam accelerator design. This is a modular design and its unique locally repetitive drive beam structure allows a flexible configuration to meet different needs. Major parameters of a conceptual 250GeV linear collider are presented. This preliminary study shows that an efficient (~5% overall), 4MW beam power collider may be achievable. The concept is extendable to the TeV scale.  
 
WEPFI090 An X-band Dielectric-based Wakefield Power Extractor 2908
 
  • C.-J. Jing, S.P. Antipov, A. Kanareykin, P. Schoessow
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • M.E. Conde, W. Gai, J.G. Power
    ANL, Argonne, USA
  • V.A. Dolgashev, J.R. Lewandowski, S.G. Tantawi, S.P. Weathersby
    SLAC, Menlo Park, California, USA
  • I. Syratchev
    CERN, Geneva, Switzerland
 
  Funding: US DoE SBIR Phase II project under Contract#DE-SC0004322
An X-band dielectric-based wakefield power extractor is under development to function as a high power rf source primarily for Two Beam Accelerator applications. A low surface electric field to gradient ratio and low fabrication cost are two main advantages of the dielectric-loaded accelerating/decelerating structure. We have designed a 12 GHz dielectric-based power extractor that has similar performance parameters to the CLIC PETS (23 mm beam channel, 240 ns pulse duration, 135 MW output per structure) using the CLIC drive beam. In order to study potential rf breakdown issues, as a first step we built a 11.424 GHz dielectric-based power extractor scaled from the 12 GHz design. A high power rf test will be conducted using the SLAC 11.424 GHz high power rf source in Dec. 2012. Results of the high power testing will be reported. Meanwhile, the 12 GHz fully featured dielectric power extractor is also under construction; construction progress and bench tests will be discussed.