Author: Boine-Frankenheim, O.
Paper Title Page
TUPPD037 Simulation Study of the Effect of the Proton Layer Thickness on TNSA 1488
  • L. Lecz
    TEMF, TU Darmstadt, Darmstadt, Germany
  • O. Boine-Frankenheim, V. Kornilov
    GSI, Darmstadt, Germany
  The LIGHT project is a collaboration of several laser and accelerator laboratories in Germany with the purpose to consolidate the theoretical, numerical and experimental investigations for the usage of laser accelerated ions in the conventional accelerators. The central facility is the PHELIX laser at GSI, Darmstadt, with a strong-field solenoid as a collimation and transport device. This contribution is devoted to the numerical investigation of the proton acceleration via the TNSA mechanism using 1D and 2D particle-in-cell electro-magnetic simulations. The phase-space distribution of the accelerated protons and co-moving electrons, which is necessary for further transport studies, is investigated for different parameters of the thin hydrogen-rich contamination layer on the rear target surface. Depending on the layer thickness the protons can be accelerated in different regimes, from the quasi-static acceleration for mono-layers up to the isothermal plasma expansion for thick layers.  
WEPPR001 Experimental Observation of Space Charge Effects in Transverse Bunch Oscillations in the SIS18 Synchrotron 2931
  • V. Kornilov, O. Boine-Frankenheim
    GSI, Darmstadt, Germany
  Coherent signals from transverse bunch oscillations in the heavy-ion synchrotron SIS18 are used for direct measurements of the space charge effect. The bunch oscillations are excited by a transverse kick and the resulting decoherence is observed. The transverse coherent motion in the SIS18 experiments is strongly affected by space charge. The bunches are long, thus the nonlinear motion in the rf bucket plays an important role and must be taken into account. The signals from the measurements are analyzed and explained using analytical and numerical models.  
WEPPR002 Intensity Thresholds for Transverse Coherent Instabilities During Proton and Heavy-Ion Operation in SIS100 2934
  • V. Kornilov, O. Boine-Frankenheim
    GSI, Darmstadt, Germany
  The SIS100 synchrotron is the central accelerator of the projected FAIR complex. It should deliver high intensity proton and heavy-ion beams to the different FAIR experiments. Coherent transverse instabilities are a potential intensity-limiting factor in SIS100. In this contribution we give a summary of the different transverse coherent effects in intense bunched beams that can be expected in the SIS100. Some of the main concerns are unstable head-tail modes, the transverse mode coupling instability, and the beam break-up instability. Space charge is an important effect that leads to Landau damping of the head-tail eigenmodes and modifies the transverse mode coupling. The growth times and thresholds for instabilities will be calculated on the basis of the present SIS100 impedance model whose main components are the resistive wall, the kickers, and the broad-band contribution. The corresponding experience from the CERN injector complex will be used for comparisons.  
WEPPR003 Longitudinal Dynamics of Intense Heavy-Ion Bunches in SIS-100 2937
  • M. Mehler, O. Boine-Frankenheim, O. Chorniy, O.K. Kester
    GSI, Darmstadt, Germany
  In the SIS-100 highest heavy-ion intensities have to be accelerated to deliver beam to the FAIR experiments. In the projected SIS-100 synchrotron the heavy ion bunches will be strongly affected by the longitudinal space charge force. Due to the limited RF bucket area all mechanisms which might cause longitudinal phase space dilution must be understood and controlled. Space charge effects, like the reduction in the RF voltage and the loss of Landau damping, have already been part of elaborate studies. It has been shown that cavity beam loading can deform the flattened bunch shape in the dual rf bucket. Among the different counter measures an inductive insert has been proposed in order to partially compensate the longitudinal space charge impedance. Optimized settings for the difference between the two rf phases in a dual rf bucket might be an option to reduce the effect of beam loading. In this contribution we will analyse the matched bunch distribution for SIS-100 parameters in single and dual rf buckets. Analytical and numerical studies of the interplay of longitudinal space charge, cavity beam loading and an inductive insert will be presented.