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Schulte, D.

Paper Title Page
TPAP003 Exploring a Nonlinear Collimation System for the LHC 877
 
  • J. Resta, A. Faus-Golfe
    IFIC, Valencia
  • R.W. Assmann, S. Redaelli, G. Robert-Demolaize, D. Schulte, F. Zimmermann
    CERN, Geneva
 
  We explore the adaptation of a nonlinear collimation system, as previously considered for linear colliders, to LHC betatron cleaning. A possible nonlinear system for LHC consists of a horizontal and vertical primary collimator located in between a pair of skew sextupoles. We discuss the modified LHC optics, the need for and optimum placement of secondary absorbers, and the simulated cleaning efficiency.  
TPPP010 Photon-Nucleon Collider Based on LHC and CLIC 1207
 
  • H. Aksakal, A.K. Ciftci
    Ankara University, Faculty of Sciences, Tandogan/Ankara
  • D. Schulte, F. Zimmermann
    CERN, Geneva
 
  We describe the scheme of a photon-nucleon collider where high-energy photons generated by Compton back-scattering off a CLIC electron beam, at either 75 GeV or 1.5 TeV, are collided with protons or ions stored in the LHC. Different design constraints for such a collider are discussed and the achievable luminosity performance is estimated.  
TPPT020 30 GHz Power Production in CTF3 1695
 
  • W. Wuensch, C. Achard, H.-H. Braun, G. Carron, R. Corsini, A. Grudiev, S.T. Heikkinen, D. Schulte, J.P.H. Sladen, I. Syratchev, F. Tecker, I. Wilson
    CERN, Geneva
 
  One of the major objectives of CTF3 (CLIC Test Facility) is the production of 30 GHz power for the high-gradient testing of CLIC accelerating structures. To this end a dedicated beam line, power generating structure and power transfer line have been designed, installed and commissioned. 52 MW of 30 GHz power with a pulse length of 74 ns and a repetition rate of 16 Hz were delivered to the high-gradient test area. This will allow operation of test accelerating structures in the coming run of CTF3 up to the nominal CLIC accelerating gradient of 150 MV/m and beyond the nominal pulse length. The system is described and the performances of the CTF3 linac, beam line and the rf components are reviewed.  
TPAP007 LHC Collimation: Design and Results from Prototyping and Beam Tests 1078
 
  • R.W. Assmann, O. Aberle, G. Arduini, A. Bertarelli, H.-H. Braun, M. Brugger, H. Burkhardt, S. Calatroni, F. Caspers, E. Chiaveri, A. Dallocchio, B. Dehning, A. Ferrari, M. Gasior, A. Grudiev, E.B. Holzer, J.-B. Jeanneret, J.M. Jimenez, Y. Kadi, R. Losito, M. Magistris, A.M. Masi, M. Mayer, E. Métral, R. Perret, C. Rathjen, S. Redaelli, G. Robert-Demolaize, S. Roesler, M. Santana-Leitner, D. Schulte, P. Sievers, E. Tsoulou, H. Vincke, V. Vlachoudis, J. Wenninger
    CERN, Geneva
  • I. Baishev, I.L. Kurochkin
    IHEP Protvino, Protvino, Moscow Region
  • G. Spiezia
    Naples University Federico II, Science and Technology Pole, Napoli
 
  The problem of collimation and beam cleaning concerns one of the most challenging aspects of the LHC project. A collimation system must be designed, built, installed and commissioned with parameters that extend the present state-of-the-art by 2-3 orders of magnitude. Problems include robustness, cleaning efficiency, impedance and operational aspects. A strong design effort has been performed at CERN over the last two years. The system design has now been finalized for the two cleaning insertions. The adopted phased approach is described and the expected collimation performance is discussed. In parallel robust and precisely controllable collimators have been designed. Several LHC prototype collimators have been built and tested with the highest beam intensities that are presently available at CERN. The successful beam tests are presented, including beam-based setup procedures, a 2 MJ robustness test and measurements of the collimator-induced impedance. Finally, an outlook is presented on the challenges that are ahead in the coming years.  
TPAP008 Measurements of the LHC Collimator Impedance with Beam in the SPS 1132
 
  • H. Burkhardt, G. Arduini, R.W. Assmann, F. Caspers, M. Gasior, A. Grudiev, O.R. Jones, T. Kroyer, E. Métral, S. Redaelli, G. Robert-Demolaize, F. Roncarolo, D. Schulte, R.J. Steinhagen, J. Wenninger, F. Zimmermann
    CERN, Geneva
 
  The transverse impedance of the LHC collimators will likely dominate the overall transverse impedance in the LHC at high energies and potentially limit the maximum intensity. A prototype collimator was recently tested in the SPS. Small, but significant tune shifts depending on the collimator position have been observed using different independent high resolution tune measurement methods. In addition trapped modes predicted from numerical simulation at the ends of the collimator jaws have been identified by bench measurement techniques as well as with the beam. We present a description of the measurements and an analysis of the results.  
RPPP009 Luminosity Tuning Bumps in the CLIC Main Linac 1141
 
  • P. Eliasson, P. Eliasson
    Uppsala University, Uppsala
  • D. Schulte
    CERN, Geneva
 
  Funding: We acknowledge the support of the European Community-Research Infrastructure Activity under the FP6 "Structuring the European Research Area" programme (CARE, contract number RII3-CT-2003-506395).

Preservation of beam emittance in the CLIC main linac is a challenging task. This requires not only beam-based alignment of the beam line components but also the use of emittance tuning bumps. In this paper the potential use of luminosity tuning bumps is explored and compared to emittance tuning bumps.

 
RPPP010 Considerations on the Design of the Decelerator of the CLIC Test Facility (CTF3) 1177
 
  • D. Schulte, I. Syratchev
    CERN, Geneva
 
  Funding: We acknowledge the support of the European Community-Research Infrastructure Activity under the FP6 "Structuring the European Research Area" programme (CARE, contract number RII3-CT-2003-506395).

One of the main aims of the CLIC Test Facility (CTF3) is to study the beam stability in the drive beam decelerator and to bench mark the performance against beam simulation codes. Particular challenges come from the large drive beam energy spread, the strong wakefields and potential beam losses. The development towards a decelerator design and the required instrumentation is described in this paper.

 
RPPP011 Different Options for Dispersion Free Steering in the CLIC Main Linac 1251
 
  • D. Schulte
    CERN, Geneva
 
  Funding: We acknowledge the support of the European Community-Research Infrastructure Activity under the FP6 "Structuring the European Research Area" programme (CARE, contract number RII3-CT-2003-506395).

Sophisticated beam-based alignment is essential in future linear colliders to preserve the beam emittance during the transport through the main linac. One such method is dispersion free steering. In this paper different options to implement this method are discussed, based on the use of different accelerating gradients, RF phases and bunch particle types during a beam pulse.

 
RPPP012 Collective Effects in the CLIC Damping Rings 1312
 
  • F. Zimmermann, M. Korostelev, D. Schulte
    CERN, Geneva
  • T.A. Agoh, K. Yokoya
    KEK, Ibaraki
 
  The small emittance, short bunch length, and high current in the CLIC damping ring could give rise to collective effects which degrade the quality of the extracted beam. In this paper, we survey a number of possible instabilities and estimate their impact on the ring performance. The effects considered include fast beam-ion instability, coherent synchrotron radiation, and electron cloud, in addition to conventional single and multi-bunch instabilities.  
RPPP014 Multi-Bunch Simulations of the ILC for Luminosity Performance Studies 1368
 
  • G.R. White
    Queen Mary University of London, London
  • D. Schulte
    CERN, Geneva
  • N.J. Walker
    DESY, Hamburg
 
  Funding: This work is supported by the Commission of the European Communities under the 6th Framework Programme "Structuring the European Research Area", contract number RIDS-011899.

To study the luminosity performance of the International Linear Collider (ILC) with different design parameters, a simulation was constructed that tracks a multi-bunch representation of the beam from the Damping Ring extraction through to the Interaction Point. The simulation code PLACET is used to simulate the LINAC, MatMerlin is used to track through the Beam Delivery System and GUINEA-PIG for the beam-beam interaction. Included in the simulation are ground motion and wakefield effects, intra-train fast feedback and luminosity-based feedback systems. To efficiently study multiple parameters/multiple seeds, the simulation is deployed on the Queen Mary High-Throughput computing cluster at Queen Mary, University of London, where 100 simultaneous simulation seeds can be run.

 
FPAP001 Electron Cloud Build-Up Study for DAFNE 779
 
  • C. Vaccarezza, R. Cimino, A. Drago, M. Zobov
    INFN/LNF, Frascati (Roma)
  • G. Bellodi
    CCLRC/RAL/ASTeC, Chilton, Didcot, Oxon
  • K. Ohmi
    KEK, Ibaraki
  • M.T.F. Pivi
    SLAC, Menlo Park, California
  • G. Rumolo
    GSI, Darmstadt
  • D. Schulte, F. Zimmermann
    CERN, Geneva
 
  After the first experimental observations compatible with the presence of the electron cloud effect in the DAFNE positron ring, a more systematic study has been performed regarding the e-cloud build-up and related instability. The measured field map of the magnetic field has been taken into account in the simulation for elements present in the four 10 m long bending sections, representing 40% of the whole positron ring. The simulation results obtained with different codes are presented and compared with the recent experimental observations performed on the beam instabilities and the vacuum behavior of the positron ring.  
FPAP013 Emittance Growth Caused by Electron Cloud Below the “Fast TMCI” Threshold: Numerical Noise or True Physics? 1344
 
  • E. Benedetto, E. Benedetto
    Politecnico di Torino, Torino
  • G. Franchetti
    GSI, Darmstadt
  • K. Ohmi
    KEK, Ibaraki
  • D. Schulte, F. Zimmermann
    CERN, Geneva
 
  Simulations show a persisting slow emittance growth for electron cloud densities below the threshold of the fast Transverse Mode Coupling type instability, which could prove important for proton beams with negligible radiation damping, such as in the LHC. We report on a variety of studies performed to quantify the contributions to the simulated emittance growth from numerical noise in the PIC module and from an artificial resonance excitation due to the finite number of kicks per turn applied for modeling the cloud-bunch interaction.  
FPAP014 Electron Cloud Measurements in the SPS in 2004 1371
 
  • D. Schulte, G. Arduini, V. Baglin, J.M. Jimenez, F. Zimmermann
    CERN, Geneva
 
  Novel measurements of the electron cloud have been performed in the SPS in 2004. In this machine the beam consists of a number of short bunch trains. By varying the distance between these trains it is possible to witness the survival of the electrons after the bunch passage. In this paper, results from simulations and experiments are compared.  
FPAT002 Automatic Steering for the CTF3 Linear Accelerator 814
 
  • R.D. Lifshitz
    Technion, Haifa
  • D. Schulte
    CERN, Geneva
 
  Funding: We acknowledge the support of the European Community-Research Infrastructure Activity under the FP6 "Structuring the European Research Area" programme (CARE, contract number RII3-CT-2003-506395)

A system for automatic beam steering has been implemented at the CTF3 linear accelerator. Beam position readings are logged while corrector magnet strengths are scanned over a given range, thus giving a steering response measurement. Assuming linearity, a response matrix is constructed and used to automatically optimize the beam trajectory along the linac. Using a simple BPM-reading minimization for trajectory correction, this system has been tested in the 2004 CTF3 summer run. Although not in routine operation, it has already proved useful as a tool for the machine setup and operation. In this paper, the automatic steering system for the CTF3 linac is introduced, trajectory correction results are presented, and the agreement with a computer model of the machine is discussed.

 
RPPE001 The CARE Accelerator R&D Programme in Europe 749
 
  • O. Napoly, R. Aleksan, A. Devred
    CEA/DSM/DAPNIA, Gif-sur-Yvette
  • A. Den Ouden
    Twente University, Laser Physics and Non-Linear Optics Group, Enschede
  • R. Garoby, R. Losito, L. Rinolfi, F. Ruggiero, W. Scandale, D. Schulte, M. Vretenar
    CERN, Geneva
  • T. Garvey, F. Richard
    LAL, Orsay
  • A. Ghigo
    INFN/LNF, Frascati (Roma)
  • E. Gschwendtner
    CUI, Geneva
  • H. Mais, D. Proch
    DESY, Hamburg
  • V. Palladino
    INFN-Napoli, Napoli
 
  Funding: This work is supported by the European Community-Research Infrastructure Activity under the FP6 “Structuring the European Research Area” programme (CARE, contract number RII3-CT-2003-506395).

CARE, an ambitious and coordinated programme of accelerator research and developments oriented towards HEP projects, has been launched in January 2004 by the main European laboratories and the European Commission within the 6th Framework Programme. This programme aims at improving existing infrastructures dedicated to future projects such as linear colliders, upgrades of hadron colliders and high intensity proton drivers. An important part of this programme is devoted to advancing the performance of the superconducting technology, both in the fields of RF cavities for electron and proton acceleration and of high field magnets, as well as to developing high intensity electron and proton injectors. We describe the R&D plans of the four main R&D activities and report on the results and progress obtained so far.

 
RPPP003 Proposal of the Next Incarnation of Accelerator Test Facility at KEK for the International Linear Collider 874
 
  • H. Hayano, S. Araki, H. Hayano, Y. Higashi, Y. Honda, K.-I. Kanazawa, K. Kubo, T. Kume, M. Kuriki, S. Kuroda, M. Masuzawa, T. Naito, T. Okugi, R. Sugahara, T. Tauchi, N. Terunuma, N. Toge, J.U. Urakawa, V.V. Vogel, H. Yamaoka, K. Yokoya
    KEK, Ibaraki
  • I.V. Agapov, G.A. Blair, G.E. Boorman, J. Carter, C.D. Driouichi, M.T. Price
    Royal Holloway, University of London, Surrey
  • D.A.-K. Angal-Kalinin, R. Appleby, J.K. Jones, A. Kalinin
    CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire
  • P. Bambade
    LAL, Orsay
  • K.L.F. Bane, A. Brachmann, T.M. Himel, T.W. Markiewicz, J. Nelson, N. Phinney, M.T.F. Pivi, T.O. Raubenheimer, M.C. Ross, R.E. Ruland, A. Seryi, C.M. Spencer, P. Tenenbaum, M. Woodley
    SLAC, Menlo Park, California
  • S.T. Boogert, A. Liapine, S. Malton
    UCL, London
  • H.-H. Braun, D. Schulte, F. Zimmermann
    CERN, Geneva
  • P. Burrows, G.B. Christian, S. Molloy, G.R. White
    Queen Mary University of London, London
  • J.Y. Choi, J.Y. Huang, H.-S. Kang, E.-S. Kim, S.H. Kim, I.S. Ko
    PAL, Pohang, Kyungbuk
  • S. Danagoulian
    North Carolina A&T State University, Greensboro, North Carolina
  • N. Delerue, D.F. Howell, A. Reichold, D. Urner
    OXFORDphysics, Oxford, Oxon
  • J. Gao, W. Liu, G. Pei, J.Q. Wang
    IHEP Beijing, Beijing
  • B.I. Grishanov, P.L. Logachev, F.V. Podgorny, V.I. Telnov
    BINP SB RAS, Novosibirsk
  • J.G. Gronberg
    LLNL, Livermore, California
  • Y. Iwashita, T. Mihara
    Kyoto ICR, Uji, Kyoto
  • M. Kumada
    NIRS, Chiba-shi
  • S. Mtingwa
    North Carolina University, Chapel Hill, North Carolina
  • O. Napoly, J. Payet
    CEA/DSM/DAPNIA, Gif-sur-Yvette
  • T.S. Sanuki, T.S. Suehara
    University of Tokyo, Tokyo
  • T. Takahashi
    Hiroshima University, Higashi-Hiroshima
  • E.T. Torrence
    University of Oregon, Eugene, Oregon
  • N.J. Walker
    DESY, Hamburg
 
  The realization of the International Linear Collider (ILC) will require the ability to create and reliably maintain nanometer size beams. The ATF damping ring is the unique facility where ILC emittancies are possible. In this paper we present and evaluate the proposal to create a final focus facility at the ATF which, using compact final focus optics and an ILC-like bunch train, would be capable of achieving 35nm beam size. Such a facility would enable the development of beam diagnostics and tuning methods, as well as the training of young accelerator physicists.