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Hofmann, I.

Paper Title Page
TUPAN012 High Intensity Heavy Ion Beam Emittance Measurements at the GSI UNILAC 1413
 
  • W. B. Bayer, W. Barth, L. A. Dahl, P. Forck, P. Gerhard, L. Groening, I. Hofmann, S. Yaramyshev
    GSI, Darmstadt
  • D.-O. Jeon
    ORNL, Oak Ridge, Tennessee
 
  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).

The GSI UNILAC, a heavy ion linac originally dedicated for low current beam operation, together with the synchrotron SIS 18 will serve as an high current injector for FAIR (International Facility for Antiproton and Ion Research). The UNILAC post stripper accelerator consists of five Alvarez tanks with a final energy of 11.4 MeV/u. In order to meet the requirements of FAIR (15emA 238U28+, transverse normalised emittances of 0.8mm mrad and 2.5mm mrad) an UNILAC upgrade program is foreseen to increase the primary beam intensity as well as the beam brilliance. A detailed understanding of the beam dynamics during acceleration and transport of space charge dominated beams is necessary. For this purpose the study of the beam brilliance dependency on the phase advances in the Alvarez DTL is suited. Machine investigations were performed with various beam diagnostics devices established in the UNILAC. Measurements done in 2006 using an high intensity heavy ion beam coincide with the beam dynamics work package of the European JRA "High Intensity Pulsed Proton Injector" (HIPPI). Results of these measurements are presented as well as corresponding beam dynamics simulations.

 
THPAN016 Improving the SIS18 Performance by use of the Orbit Response Method 3256
 
  • A. S. Parfenova, G. Franchetti, I. Hofmann, C. Omet
    GSI, Darmstadt
  • S.-Y. Lee
    IUCF, Bloomington, Indiana
 
  The SIS18 will be used as a booster for the new FAIR facility SIS100. A well-controlled linear optics of the SIS18 is necessary for further optimisation studies of nonlinear dynamics, resonance induced beam loss, dynamic aperture and nonlinear error measurements. The analysis of the orbit response matrix (ORM) is a powerful tool to calibrate the linear lattice models. We present results of several measurements on the SIS18 using the ORM and discuss the achieved improvement of the SIS18 performance.  
THPAN017 Scaling Laws for Space Charge Driven Resonances 3259
 
  • I. Hofmann, G. Franchetti
    GSI, Darmstadt
 
  Intrinsic fourth order space charge resonances may occur in linear as well as circular accelerators. The difference resonance ("emittance exchange" or "Montague" resonance) and the fourth order structure resonance lead to emittance variations depending on the strength of space charge, the crossing rate and the lattice. We present scaling laws for the Montague coupling resonance and for the fourth order structure resonance in terms of simple power law expressions that allow a straightforward application in design of accelerators subject to these mechanism.  
THPAN018 Stability Thresholds for Transverse Dipole Modes with Nonlinear Space Charge, Chromaticity and Octupoles 3262
 
  • V. Kornilov, O. Boine-Frankenheim, I. Hofmann
    GSI, Darmstadt
 
  Funding: Work supported by EU design study (contract 515873 -DIRACsecondary-Beams)

Transverse stability due to combinations of chromaticity effect, nonlinear space charge and octupoles of different polarities plays an important role in the determination of the impedance budget for the FAIR synchrotrons. Different analytic approaches [*,**,etc.] have been suggested, for which no direct comparison has been made so far. In order to clarify this issue we perform numerical investigations employing the particle tracking code PATRIC and compare results of simulation scans with predictions of a dispersion relation. Space charge effects within self-consistent and 'frozen' models are used for comparisons, connection to beam transfer function studies is addressed.

* D. Moehl, CERN/PS 95-08 (DI), (1995)** M. Blaskiewicz, Phys. Rev. ST Accel. Beams 4, 044202, (2001)

 
THPAN030 Transverse Self-Consistent Modeling of a 3D Bunch in SIS100 with MICROMAP 3292
 
  • C. Benedetti, S. Rambaldi, G. Turchetti
    Bologna University, Bologna
  • G. Franchetti, I. Hofmann
    GSI, Darmstadt
 
  Funding: EU-DESIGN STUDY (contract 515873 - DIRACsecondary-Beams)

We present the upgrade of the MICROMAP beam dynamics simulation library to include a 2 1/2 D space charge modeling of a 3D bunch using local slices in z. We discuss the parallelization technique, the performances, several tests and comparison with existing well-established analytical/numerical results in order to validate the code. An application to the SIS100 synchrotron of the FAIR project at GSI is outlined.