Author: Rimmer, R.A.
Paper Title Page
TUP094 Novel Crab Cavity RF Design 1006
 
  • M.L. Neubauer, A. Dudas, R. Sah
    Muons, Inc, Batavia, USA
  • R.A. Rimmer, H. Wang
    JLAB, Newport News, Virginia, USA
 
  Funding: Supported in part by DOE SBIR grant DE-SC0005444
A 20-50 MV integrated transverse voltage is required for the Electron-Ion Collider. The most promising of the crab cavity designs that have been proposed in the last five years are the TEM type crab cavities because of the higher transverse impedance. The TEM design approach is extended here to a hybrid crab cavity that includes the input power coupler as an integral part of the design. A prototype was built with Phase I monies and tested at JLAB. The results reported on, and a system for achieving 20-50 MV is proposed.
 
 
WEP249 Intense Muon Beams for Experiments at Project X 1951
 
  • C.M. Ankenbrandt, R.P. Johnson, C. Y. Yoshikawa
    Muons, Inc, Batavia, USA
  • V.S. Kashikhin, D.V. Neuffer
    Fermilab, Batavia, USA
  • J. Miller
    BUphy, Boston, Massachusetts, USA
  • R.A. Rimmer
    JLAB, Newport News, Virginia, USA
 
  Funding: Supported in part by DOE SBIR grant DE-SC00002739
A coherent approach for providing muon beams to several experiments for the intensity-frontier program at Project X is described. Concepts developed for the front end of a muon collider/neutrino factory facility, such as phase rotation and ionization cooling, are applied, but with significant differences. High-intensity experiments typically require high-duty-factor beams pulsed at a time interval commensurate with the muon lifetime. It is challenging to provide large RF voltages at high duty factor, especially in the presence of intense radiation and strong magnetic fields, which may preclude the use of superconducting RF cavities. As an alternative, cavities made of materials such as ultra-pure Al and Be, which become very good - but not super - conductors at cryogenic temperatures, can be used.
 
 
THP212 Superconducting Cavity Design for Short-Pulse X-Rays at the Advanced Photon Source 2516
 
  • G.J. Waldschmidt, B. Brajuskovic, R. Nassiri
    ANL, Argonne, USA
  • G. Cheng, J. Henry, J.D. Mammosser, R.A. Rimmer, H. Wang
    JLAB, Newport News, Virginia, USA
 
  Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
Superconducting cavities have been analyzed for the short-pulse x-ray (SPX) project at the Advanced Photon Source (APS). Due to the strong damping requirements in the APS storage ring, single-cell superconducting cavities have been designed. The geometry has been optimized for lower-order and higher-order mode damping, reduced peak surface magnetic fields, and compact size. The integration of the cavity assembly, with dampers and waveguide input coupler, into a cryomodule will be discussed.
 
 
WEOBS5 Status of the Short-Pulse X-ray Project (SPX) at the Advanced Photon Source (APS) 1427
 
  • R. Nassiri, N.D. Arnold, G. Berenc, M. Borland, D.J. Bromberek, Y.-C. Chae, G. Decker, L. Emery, J.D. Fuerst, A.E. Grelick, D. Horan, F. Lenkszus, R.M. Lill, V. Sajaev, T.L. Smith, G.J. Waldschmidt, G. Wu, B.X. Yang, A. Zholents
    ANL, Argonne, USA
  • J.M. Byrd, L.R. Doolittle, G. Huang
    LBNL, Berkeley, California, USA
  • G. Cheng, G. Ciovati, J. Henry, P. Kneisel, J.D. Mammosser, R.A. Rimmer, L. Turlington, H. Wang
    JLAB, Newport News, Virginia, USA
 
  Funding: Work at Argonne is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11354.
The Advanced Photon Source Upgrade project (APS-U) at Argonne includes implementation of Zholents’* deflecting cavity scheme for production of short x-ray pulses. This is a joint project between Argonne National Laboratory, Thomas Jefferson National Laboratory, and Lawrence Berkeley National Laboratory. This paper describes performance characteristics of the proposed source and technical issues related to its realization. Ensuring stable APS storage ring operation requires reducing quality factors of these modes by many orders of magnitude. These challenges reduce to those of the design of a single-cell SC cavity that can achieve the desired operating deflecting fields while providing needed damping of all these modes. The project team is currently prototyping and testing several promising designs for single-cell cavities with the goal of deciding on a winning design in the near future.
*A. Zholents et al., NIM A 425, 385 (1999).
 
slides icon Slides WEOBS5 [1.730 MB]  
 
WEOCS7 Crab Cavity and Cryomodule Prototype Development for the Advanced Photon Source 1472
 
  • H. Wang, G. Cheng, G. Ciovati, W.A. Clemens, J. Henry, P. Kneisel, P. Kushnick, K. Macha, J.D. Mammosser, R.A. Rimmer, G. Slack, L. Turlington
    JLAB, Newport News, Virginia, USA
  • R. Nassiri, G.J. Waldschmidt, G. Wu
    ANL, Argonne, USA
 
  Funding: Work is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11354.
Two single-cell, superconducting, squashed elliptical crab cavities with waveguides to damp Higher Order Modes (HOM) and Lower Order Mode (LOM) have been designed and prototyped for the Short Pulse X-ray (SPX) project at the Advanced Photon Source (APS). The Baseline cavity with LOM damper on the beam pipe has been vertically tested and exceeded its performance specification with over 0.5MV deflecting voltage. The Alternate cavity design which uses an “on-cell” waveguide damper is preferred due to its larger LOM impedance safety margin. Its prototype cavity has been fabricated by a Computer Numerical Controlled (CNC) machine and is subject to further testing. The conceptual design, layout and analysis for various cryomodule components are presented.
 
slides icon Slides WEOCS7 [7.008 MB]  
 
THOBN3 Proof-of-Principle Experiment for FEL-based Coherent Electron Cooling 2064
 
  • V. Litvinenko, I. Ben-Zvi, J. Bengtsson, A.V. Fedotov, Y. Hao, D. Kayran, G.J. Mahler, W. Meng, T. Roser, B. Sheehy, R. Than, J.E. Tuozzolo, G. Wang, S.D. Webb, V. Yakimenko
    BNL, Upton, Long Island, New York, USA
  • G.I. Bell, D.L. Bruhwiler, B.T. Schwartz
    Tech-X, Boulder, Colorado, USA
  • A. Hutton, G.A. Krafft, M. Poelker, R.A. Rimmer
    JLAB, Newport News, Virginia, USA
 
  Funding: This work is supported the U.S. Department of Energy
Coherent electron cooling (CEC) has a potential to significantly boost luminosity of high-energy, high-intensity hadron-hadron and electron-hadron colliders*. In a CEC system, a hadron beam interacts with a cooling electron beam. A perturbation of the electron density caused by ions is amplified and fed back to the ions to reduce the energy spread and the emittance of the ion beam. To demonstrate the feasibility of CEC we propose a proof-of-principle experiment at RHIC using one of JLab’s SRF cryo-modules. In this paper, we describe the experimental setup for CeC installed into one of RHIC's interaction regions. We present results of analytical estimates and results of initial simulations of cooling a gold-ion beam at 40 GeV/u energy via CeC.
* Vladimir N. Litvinenko, Yaroslav S. Derbenev, Physical Review Letters 102, 114801
 
slides icon Slides THOBN3 [1.379 MB]  
 
THP093 Design Status of MEIC at JLab 2306
 
  • Y. Zhang, S. Ahmed, S.A. Bogacz, P. Chevtsov, Y.S. Derbenev, A. Hutton, G.A. Krafft, R. Li, F. Marhauser, V.S. Morozov, F.C. Pilat, R.A. Rimmer, Y. Roblin, T. Satogata, M. Spata, B. Terzić, M.G. Tiefenback, H. Wang, B.C. Yunn
    JLAB, Newport News, Virginia, USA
  • S. Abeyratne, B. Erdelyi
    Northern Illinois University, DeKalb, Illinois, USA
  • D.P. Barber
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  • A.M. Kondratenko
    GOO Zaryad, Novosibirsk, Russia
  • S.L. Manikonda, P.N. Ostroumov
    ANL, Argonne, USA
  • H. K. Sayed
    ODU, Norfolk, Virginia, USA
  • M.K. Sullivan
    SLAC, Menlo Park, California, USA
 
  Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
An electron-ion collider (MEIC) is envisioned as the primary future of the JLab nuclear science program beyond the 12 GeV upgraded CEBAF. The present MEIC design selects a ring-ring collider option and covers a CM energy range up to 51 GeV for both polarized light ions and un-polarized heavy ions, while higher CM energies could be reached by a future upgrade. The MEIC stored colliding ion beams, which will be generated, accumulated and accelerated in a green field ion complex, are designed to match the stored electron beam injected at full energy from the CEBAF in terms of emittance, bunch length, charge and repetition frequency. This design strategy ensures a high luminosity above 1034 s−1cm-2. A unique figure-8 shape collider ring is adopted for advantages of preserving ion polarization during acceleration and accommodation of a polarized deuteron beam for collisions. Our recent effort has been focused on completing this conceptual design as well as design optimization of major components. Significant progress has also been made in accelerator R&D including chromatic correction and dynamical aperture, beam-beam, high energy electron cooling and polarization tracking.