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Weiland, T.

Paper Title Page
MPPP002 Stochastic Cooling Electrodes for a Wide Velocity Range in the CR 799
 
  • F. Nolden, B.  Franzke, C. Peschke
    GSI, Darmstadt
  • M.C. Balk, R. Schuhmann, T. Weiland
    TEMF, Darmstadt
  • F. Caspers, L. Thorndahl
    CERN, Geneva
 
  The CR storage ring is part of the FAIR project at GSI. It serves as a first stage of stochastic cooling for secondary rare isotopes at v/c=0.83 as well as for antiprotons at v/c=0.97. To avoid the installation of dedicated structures for each kind of beam, electrodes have been developed which are usable for both beams. They are based on slotline structures mounted perpendicular to the beam. They are shorted at the ends, and their signal is extracted by two striplines on the rear side, placed a quarter wavelength away from the open ends. The width of the structures can be adjusted to the initial betatron oscillation amplitudes. Their length is 24 mm, and the signal from many of these structures mounted in a row can be combined. The signal combination can be matched to the different beam velocities. The paper shows results from field calculations, prototype tests, and estimates of the signal combination efficiency. The beam impedance of the novel structures is compared with the superelectrodes applied in the former CERN AC and with the slow-wave structures currently installed in the FNAL Debuncher.  
MPPP023 Numerical Calculation of Coupling Impedances for Kicker Modules 1820
 
  • B. Doliwa, H. De Gersem, T. Weiland
    TEMF, Darmstadt
 
  Funding: Work supported in part by DFG under contract GraKo 410 and GSI, Darmstadt.

Maintaining the impedance budget is an important task in the planning of any new accelerator facility. While estimates from analytical computations and measurements play a central role in doing so, numerical calculations have become an important alternative today. On the basis of Finite Integration Theory, we have developed a simulation tool for the direct computation of coupling impedances in the frequency domain. After discussing the special features of our code as compared to commercial programs, we present our results for cases where coupling impedances have been obtained from another source, e.g. experiment. In particular, we consider the longitudinal and transverse impedances of the SNS extraction kicker and present investigations related to the injection/extraction system of the future heavy-ion synchrotron at GSI.

 
TPAT008 Numerical Dispersion Error Reduction in EM Calculations for Accelerators 1114
 
  • T. Lau, E. Gjonaj, T. Weiland
    TEMF, Darmstadt
  • I. Zagorodnov
    DESY, Hamburg
 
  Funding: Deutsches Elektronen-Synchrotron DESY

In this contribution novel numerical algorithms with no dispersion along the beam axis are investigated. This property is of interest for the long-time calculation of electromagnetic fields in accelerators. Instead of increasing the spatial stencil of the Yee scheme the compared methods modify the time-stepping algorithm.The results are compared on several test examples. As a practical application the electromagnetic field of a very short bunch inside a cavity is calculated.

 
WPAP008 Simulation for a New Polarized Electron Injector (SPIN) for the S-DALINAC 1117
 
  • B. Steiner, W.F.O. Müller, T. Weiland
    TEMF, Darmstadt
  • J. Enders, H.-D. Gräf, A. Richter, M. Roth
    TU Darmstadt, Darmstadt
 
  Funding: Work supported in part by DFG under contract SFB 634 and DESY, Hamburg.

The Superconducting DArmstädter LINear ACcelerator (S-DALINAC) is a 130 MeV recirculating electron accelerator serving several nuclear and radiation physics experiments. For future tasks, the 250 keV thermal electron source should be completed by a 100 keV polarized electron source. Therefore a new low energy injection concept for the S-DALINAC has to be designed. The main components of the injector are a polarized electron source, an alpha magnet, a Wien filter spin-rotator and a Mott polarimeter. In this paper we report over the first simulation and design results. For our simulations we used the TS2 and TS3 modules of the CST MAFIA (TM) programme which are PIC codes for two and three dimensions and the CST PARTICLE STUDIO (TM).

 
WPAP006 Recent Developments at PITZ 1012
 
  • M. Krasilnikov, K. Abrahamyan, G. Asova, J.W. Baehr, G. Dimitrov, U. Gensch, H.-J. Grabosch, J.H. Han, S. Khodyachykh, S. Liu, V. Miltchev, A. Oppelt, B. Petrosyan, S. Riemann, L. Staykov, F. Stephan
    DESY Zeuthen, Zeuthen
  • W. Ackermann, W.F.O. Müller, S. Schnepp, T. Weiland
    TEMF, Darmstadt
  • J.-P. Carneiro, K. Floettmann, S. Schreiber
    DESY, Hamburg
  • M.V. Hartrott, E. Jaeschke, D. Kraemer, D. Lipka, R. Richter
    BESSY GmbH, Berlin
  • P. Michelato, L. Monaco, C. Pagani, D. Sertore
    INFN/LASA, Segrate (MI)
  • J.R. Roensch, J. Rossbach
    Uni HH, Hamburg
  • W. Sandner, I. Will
    MBI, Berlin
  • I. Tsakov
    INRNE, Sofia
 
  The ability to produce high brightness electron beams as required for modern Free Electron Lasers (FELs) has been demonstrated during the first stage of the Photo Injector Test Facility at DESY Zeuthen (PITZ1). The electron source optimization at PITZ1 was successfully completed, resulting in the installation of the PITZ rf gun at the VUV-FEL (DESY, Hamburg). One of the main goals of the second stage of PITZ (PITZ2) is to apply higher gradients in the rf gun cavity in order to obtain smaller beam emittance by faster acceleration of the space charge dominated beams. In order to reach the required gradients a 10 MW klystron has to be installed and the gun cavity has to be conditioned for higher peak power. Another important goal of PITZ2 is a detailed study of the emittance conservation principle by using proper electron beam acceleration with a booster. Further photo injector optimization, including update of the photocathode laser and diagnostic tools, is foreseen as well. Recent progress on the PITZ developments will be reported.  
FPAT079 Data Base Extension for the Ensemble Model Using a Flexible Implementation 4036
 
  • W. Ackermann, T. Weiland
    TEMF, Darmstadt
 
  Funding: Work supported by DESY, Hamburg.

To guarantee an adequate design and a proper functionality of various machine components it is of great importance to perform detailed studies of charged particle transport. However, it is often not necessary to initiate individual kinetic simulations. When the evolution of integral quantities is of research interest, it is worth treating an investigated particle ensemble as a whole and applying a macroscopic formulation. Using a collision-less kinetic approach, the simplified model is derived from the well-known Vlasov equation. Instead of solving directly this equation, one can use moments of the density function obtained by means of an averaging process. This formalism had been implemented into the beam dynamics simulation program V-Code and a fundamental database of various beam line elements like cavities, drift spaces, solenoids, quadrupoles and steerers was set up. A flexible realization of the C++ code representing the cavities and the drift spaces can be automatically used for an arbitrary order of moments applying a symbolic algebra program. A useful extension to the remaining beam line elements together with appropriate simulation results is presented in the paper.

 
RPPP036 A Test Facility for the International Linear Collider at SLAC End Station A for Prototypes of Beam Delivery and IR Components 2461
 
  • M. Woods, R.A. Erickson, J.C. Frisch, C. Hast, R.K. Jobe, L. Keller, T.W. Markiewicz, T.V.M. Maruyama, D.J. McCormick, J. Nelson, N. Phinney, T.O. Raubenheimer, M.C. Ross, A. Seryi, S. Smith, Z. Szalata, P. Tenenbaum, M. Woodley
    SLAC, Menlo Park, California
  • D.A.-K. Angal-Kalinin, C.D. Beard, F.J. Jackson, A. Kalinin
    CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
  • R. Arnold
    University of Massachusetts, Amherst
  • D. Bailey
    ,
  • R.J. Barlow, G.Yu. Kourevlev, A. Mercer
    UMAN, Manchester
  • S.T. Boogert, A. Liapine, S. Malton, D.J. Miller, M.W. Wing
    UCL, London
  • P. Burrows, G.B. Christian, C.C. Clarke, A.F. Hartin, S. Molloy, G.R. White
    Queen Mary University of London, London
  • D. Burton, N. Shales, J. Smith, A. Sopczak, R. Tucker
    Microwave Research Group, Lancaster University, Lancaster
  • D. Cussans
    University of Bristol, Bristol
  • C. Densham, J. Greenhalgh
    CCLRC/DL, Daresbury, Warrington, Cheshire
  • M.H. Hildreth
    Notre Dame University, Notre Dame, Iowa
  • Y.K. Kolomensky
    UCB, Berkeley, California
  • W.F.O. Müller, T. Weiland
    TEMF, Darmstadt
  • N. Sinev, E.T. Torrence
    University of Oregon, Eugene, Oregon
  • M.S. Slater, M.T. Thomson, D.R. Ward
    University of Cambridge, Cambridge
  • Y. Sugimoto
    KEK, Ibaraki
  • S.W. Walston
    LLNL, Livermore, California
  • N.K. Watson
    Birmingham University, Birmingham
  • I. Zagorodnov
    DESY, Hamburg
  • F. Zimmermann
    CERN, Geneva
 
  Funding: U.S. Department of Energy.

The SLAC Linac can deliver damped bunches with ILC parameters for bunch charge and bunch length to End Station A (ESA). A 10Hz beam at 28.5 GeV energy can be delivered to ESA, parasitic with PEP-II operation. During the engineering design phase for the ILC over the next 5 years, we plan to use this facility to prototype and test key components of the Beam Delivery System (BDS) and Interaction Region (IR). We discuss our plans for this ILC Test Facility and preparations for carrying out experiments related to Collimator Wakefields, Materials Damage Tests and Energy Spectrometers. We also plan an IR Mockup of the region within 5 meters of the ILC Interaction Point to investigate effects from backgrounds and beam rf higher-order modes (HOMs).