A   B   C   D   E   F   G   H   I   K   L   M   O   P   Q   R   S   T   V   W    

linac

Paper Title Other Keywords Page
IT07 Bunch Length Measurements electron, laser, radiation, gun 19
 
  • M. Geitz
    DESY, Deutsches Elektronen Synchrotron, Hamburg, Germany
  An rf photo-injector in combination with a magnetic bunch compressor is suited to produce high-charged sub-picosecond electron bunches required for electron-drive linacs for VUV and X-ray FELs. This report summarizes time- and frequency domain bunch length measurement techniques with sub-picosecond resolution.  
 
IT09 Diagnostics in Heavy Ion Machines ion, heavy-ion, diagnostics, electron 28
 
  • P. Strehl
    GSI, Gesellschaft für Schwerionenforschung, Darmstadt, Germany
  An overview of the measurements of most important beam parameters in heavy ion machines is given. The special characteristics of heavy ions concerning the great variety of parameters with respect to the type of accelerator (linac, circular machine), the species of accelerated ions as well as their energy, beam intensity, beam emittance and time structure are considered. The consequences for the design of beam diagnostic systems are discussed. Typical examples of measuring systems are given. Experimental results taken during the long operating time of the GSI facilities, covering a wide range of parameters, are reported.  
 
IT11 Beam Diagnostics, Old and New
This is essentially a repeat of 'Beam Diagnostics Revisited', invited talk given at EPAC, Stockholm, June 1998 		diagnostics, emittance, ion, injection 33
 
  • H. Koziol
    CERN, Geneva, Switzerland
  The performance of accelerators and storage rings depends critically on the completeness and quality of their beam diagnostic systems. It is essential to equip them from inception with all the instruments providing the information on the properties and the behaviour of the beams, needed during running-in, in operation, and for development of performance towards the design goal and often well beyond. Most of the instruments have proven their worth since decades, but their power has been increased through the modern means of data acquisition and treatment. A few new instruments have made their appearance in recent years, some still under development and scrutiny for their operational value and precision. The multi-accelerator chains of today’s and tomorrow’s big colliders have tight tolerances on beam loss and emittance blow-up. For beam diagnostics this means a great challenge for precision and consistency of measurements all along the chain.  
 
PS05 Recent Improvements of a Cryogenic Current Comparator for nA Ion Beams with High Intensity Dynamics ion, pick-up, heavy-ion, instrumentation 109
 
  • A. Peters, H. Reeg, P. Forck
    GSI, Gesellschaft für Schwerionenforschung, Darmstadt, Germany
  • W. Vodel, R. Neubert
    FSU Jena, Institut für Festkörperphysik, Friedrich Schiller Universität, Jena, Germany
  Former measurements of extracted ion beams from the GSI heavy ion synchrotron SIS showed large current fluctuations in the microsecond region with a high peak-to-average ratio. To adapt our Cryogenic Current Comparator (CCC) to this time structure the detector’s electronics have been carefully modified. The most important improvement of the new DC SQUID system affects the enlargement of the bandwidth and the slew rate of the measuring system. In addition the existing data acquisition system for e.g. SEMs (Secondary Emission Monitors) was extended to digitize the CCC signals simultaneously. Measurements of Argon beams will be shown to demonstrate the improved capabilities of the upgraded Cryogenic Current Comparator.  
 
PS07 Trajectory Measurements in the DAΦNE Transfer Lines pick-up, damping, injection, vacuum 115
 
  • A. Stella, C. Milardi, M. Serio
    INFN-LNL, Laboratori Nazionali di Legnaro, Legnaro, Italy
  An improved beam position monitor system has been installed in the Transfer Lines (TL) connecting the DAΦNE Linac to the collider Main Rings through the Damping Ring, to monitor the beam trajectory and optimize the transmission efficiency. Signals from stripline type beam position monitors are stretched, sampled through Track & Hold circuits and digitized to 12 bits. The sampling stage is triggered, according to the timing of the desired beam, to measure the amplitude of the signals induced on a BPM. Hardware control, data collection and reconstruction of the beam position along the Transfer Lines are performed by the DAΦNE Control System on a VME standard local processor. Design issues, implementation and performance of the system are presented.  
 
PT07 Emittance measurements at the new UNILAC-pre-stripper using a pepper-pot with a PC-controlled CCD-camera emittance, ion, laser, ion-source 171
 
  • M. Dolinska, M. Domke, P. Forck, T. Hoffmann, D. Liakin, A. Peters, P. Strehl
    GSI, Gesellschaft für Schwerionenforschung, Darmstadt, Germany
  The complex mathematical algorithms and procedures to extract emittance data from intensity distributions measured with a single shot pepper-pot device are described. First results of mathematical evaluation from the commissioning of the new GSI pre-stripper linac structures are presented.  
 
PT10 Emittance and dispersion measurements at TTF emittance, quadrupole, dipole, acceleration 180
 
  • M. Castellano, A. Cianchi, V.A. Verzilov
    INFN-LNF, Laboratori Nazionali di Frascati dell'INFN, Frascati, Italy
  It is well known that beam dispersion , along with the Twiss parameters and emittance, contributes to the beam spot size. So that, in general, anomalous dispersion is an undesirable event and must be minimized by careful tuning the machine. If not, when the spot size is used to infer beam emittances, as it is the case of the "quadrupole scan" method, basically employed at TTF, the unknown dispersion can lead to overestimated values for the emittance. This paper presents the first attempt to determine the dispersion function at several points of the TTF Linac and to separate its contribution to the local emittance measurement, performed by means of the OTR imaging technique.  
 
PT14 Experience with stripline beam position monitors on the TESLA test facility LINAC quadrupole, alignment, lattice, beam-transport 190
 
  • P. Castro, P. Patteri, F. Tazzioli
    DESY, Deutsches Elektronen Synchrotron, Hamburg, Germany
  Measurement and correction of beam position are very important for the optimization of beam characteristics and alignment in the Tesla Test Facility (TTF) linac. We describe and present measurements with beam of the performance of the stripline beam position monitors (BPMs) in operation and in order to determine the beam response.  
 
PT17 Role of pre-wave zone effects in TR-based beam diagnostics radiation, diagnostics, electromagnetic-fields, background 199
 
  • V.A. Verzilov
    INFN-LNF, Laboratori Nazionali di Frascati dell'INFN, Frascati, Italy
  Transition radiation (TR) is nowadays intensively exploited by a number of techniques to characterize different beam parameters. These methods are based, sometimes implicitly, on standard formulae, and used often without paying due attention to their applicability. In particular, standard expressions are only first-order asymptotic, i.e., strictly speaking, valid at infinity. In this paper TR is examined in a spatial domain where conventional results are no more exact and variations in radiation properties are observed. Under certain conditions, for example, at long wavelengths or very high energies the effect is so considerable that should be taken into account in accurate beam measurements.