Author: Mironov, V.
Paper Title Page
TUZO02 Detailed Investigation of the 4D Phase-Space of an Ion Beam 30
 
  • H.R. Kremers, J.P.M. Beijers, S. Brandenburg, V. Mironov, S. Saminathan
    KVI, Groningen, The Netherlands
 
  A second order transfer matrix is calculated, which is used in the calculation of a 4D phase-space distribution of a 24.6 keV He1+ beam. The calculated distribution matches a 4D phase-space distribution measured with the KVI pepper pot emittance meter. The pepper pot emittance meter is installed in the image plane of a dipole magnet acting as a charge-state analyser directly downstream the KVI AECR ion source. From the second order transfer matrix simple analytical equations are derived by retaining the terms for angular coefficients. These simple equations describe the main features of the phase-space correlations in the image plane. The equations show also that the subset of the 4D phase-space distribution, selected by one pepper pot aperture, results in multiple beam-lets. Due to this successful matrix modelling we conclude that the 4D phase-space distribution measured is fully determined by the ionoptical properties of the magnet.  
slides icon Slides TUZO02 [6.348 MB]  
 
TUPP18 DECRIS-5 Ion Source for DC-110 Cyclotron Complex Results of the First Tests 74
 
  • A.A. Efremov, V. Bekhterev, S.L. Bogomolov, Yu.K. Kostyukhov, N. Lebedev, V.N. Loginov, Yu. Yazvitsky
    JINR, Dubna, Moscow Region, Russia
  • V. Mironov
    KVI, Groningen, The Netherlands
 
  The project of the DC-110 cyclotron facility to provide applied research in the nanotechnologies (track pore membranes, surface modification of materials, etc.) has been designed by the Flerov Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research (Dubna). The facility includes the isochronous cyclotron DC-110 for accelerating the intense Ar, Kr, Xe ion beams with 2.5 MeV/nucleon fixed energy. The cyclotron is equipped with system of axial injection and ECR ion source DECRIS-5, operating at the frequency of 18 GHz. The main parameters of DECRIS-5 ion source and results of the first tests are presented in this report.  
 
WEXO03 Numerical Modeling of Ion Production in ECRIS by using the Particle-in-Cell Method 82
 
  • V. Mironov, J.P.M. Beijers
    KVI, Groningen, The Netherlands
 
  To better understand the physical processes in ECRIS plasmas, we developed a Particle-in-Cell code that follows the ionization and diffusion dynamics. The basic features of the numerical model are given elsewhere*. An electron temperature of about 1 keV is needed to reproduce the experimentally observed performance of our 14 GHz ECR source. We assume that a pre-sheath is located outside the ECR zone, where the ion acceleration toward the walls occurs. Electric field inside the ECR zone is supposed to be zero. The ion production is modeled assuming the ion confinement by a ponderomotive barrier formed at the boundary of the ECR zone. The barrier height is defined by the RF radiation density at the electron resonance layer and is taken as an adjustable parameter; when the plasma becomes overdense, we set the barrier value to zero. With these assumptions, we are able to reproduce the main features of ECRIS performance, such as the saturation and decrease of highest charge state currents with increasing gas pressure, as well as response to an increase of injected RF power. Afterglow and frequency-tuning effects can be explained by introducing the ponderomotive barrier.
* V. Mironov and J. P. M. Beijers, "Three-dimensional simulations of ion dynamics in the plasma of an electron cyclotron resonance ion source", Phys. Rev. ST Accel. Beams 12, 073501 (2009).
 
slides icon Slides WEXO03 [7.032 MB]