A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z  

Leitner, M.

Paper Title Page
MOOBC02 Experiments in Warm Dense Matter using an Ion Beam Driver 140
  • F. M. Bieniosek, M. Leitner, B. G. Logan, R. More, P. N. Ni, P. K. Roy
    LBNL, Berkeley, California
  • J. J. Barnard, M. Kireeff Covo, A. W. Molvik
    LLNL, Livermore, California
  • L. Grisham
    PPPL, Princeton, New Jersey
  • H. Yoneda
    University of electro-communications, Tokyo
  Funding: Work performed under the auspices of the U. S. Dept. of Energy by LBNL, LLNL, and PPPL under Contracts No. W-7405-Eng-48, DE-AC02-05CH11231, and DE-AC02-76CH3073.

We describe near term heavy-ion beam-driven warm dense matter (WDM) experiments. Initial experiments are at low beam velocity, below the Bragg peak, increasing toward the Bragg peak in subsequent versions of the accelerator. The WDM conditions are envisioned to be achieved by combined longitudinal and transverse neutralized drift compression to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. Initial candidate experiments include an experiment to study transient darkening in the WDM regime; and a thin target dE/dx experiment to study beam energy and charge state distribution in a heated target. Further experiments will explore target temperature and other properties such as electrical conductivity to investigate phase transitions and the critical point.

slides icon Slides  
WEOCC02 Overview of warm-dense-matter experiments with intense heavy ion beams at GSI-Darmstadt 2038
  • P. N. Ni, F. M. Bieniosek, M. Leitner, B. G. Logan, R. More, P. K. Roy
    LBNL, Berkeley, California
  • J. J. Barnard
    LLNL, Livermore, California
  • A. Fernengel, A. Menzel
    TU Darmstadt, Darmstadt
  • A. Fertman, A. Golubev, B. Y. Sharkov, I. Turtikov
    ITEP, Moscow
  • D. Hoffmann, A. Hug, N. A. Tahir, A. Udrea, D. Varentsov
    GSI, Darmstadt
  • M. Kulish, D. Nikolaev, A. Ternovoy
    IPCP, Chernogolovka, Moscow region
  Recently, a series of high energy density (HED) physics experiments with heavy ion beams have been carried out at the GSI heavy ion accelerator. The ion beam spot of heating uranium beam size of about 1 mm, pulse length about 120 ns and intensity 109 particles/bunch. In these experiments, metallic solid and porous targets of macroscopic volumes were heated by intense heavy ion beams uniformly and quasi-isochorically, and temperature, pressure and expansion velocity were measured during the heating and cooling of the sample using a fast multi-channel radiation pyrometer, laser Doppler interferometer (VISAR), Michelson displacement interferometer and streak-camera-based-backlighting system. In the performed experiments target temperatures varying from 1'000 K to 12'000 K and pressure in kbar range were measured. Expansion velocities up to 2600 m/s have been registered for lead and up to 1700 m/s for tungsten targets.  
slides icon Slides  
THPAS006 A Solenoid Final Focusing System with Plasma Neutralization for Target Heating Experiments 3519
  • P. K. Roy, F. M. Bieniosek, J. E. Coleman, J.-Y. Jung, M. Leitner, B. G. Logan, P. A. Seidl, W. L. Waldron
    LBNL, Berkeley, California
  • J. J. Barnard, A. W. Molvik
    LLNL, Livermore, California
  • R. C. Davidson, P. Efthimion, E. P. Gilson, A. B. Sefkow
    PPPL, Princeton, New Jersey
  • J. A. Duersch, D. Ogata
    UCB, Berkeley, California
  • D. R. Welch
    Voss Scientific, Albuquerque, New Mexico
  Intense bunches of low-energy heavy ions have been suggested as means to heat targets to the warm dense matter regime (0.1 to 10 eV). In order to achieve the required intensity on target (~1 eV heating), a beam spot radius of approximately 0.5 mm, and pulse duration of 2 ns is required with an energy deposition of approximately 1 J/cm2. This translates to a peak beam current of 8A for ~0.4 MeV K+ ions. To increase the beam intensity on target, a plasma-filled high-field solenoid is being studied as a means to reduce the beam spot size from several mm to the sub-mm range. We are building a prototype experiment to demonstrate the required beam dynamics. The magnetic field of the pulsed solenoid is 5 to 8 T. Challenges include suitable injection of the plasma into the solenoid so that the plasma density near the focus is sufficiently high to maintain space-charge neutralization of the ion beam pulse. Initial experimental results for a peak current of ~1A will be presented.

This work was supported by the Office of Fusion Energy Sciences, of the U. S. Department of Energy under Contract No. DE-AC02-05CH11231, W-7405-Eng-48, DE-AC02-76CH3073 for HIFS-VNL.

FRPMS018 1-MeV Electrostatic Ion Energy Analyzer 3940
  • F. M. Bieniosek, M. Leitner
    LBNL, Berkeley, California
  Funding: Work performed under the auspices of the U. S. Department of Energy by the university of California, Lawrence Berkeley National Laboratory under Contract No. DE-AC03-76F00098.

We describe a high resolution (a few x 10-4) 90-degree cylindrical electrostatic energy analyzer for 1-MeV (singly ionized) heavy ions for experiments in the Heavy Ion Fusion Science Virtual National Laboratory. By adding a stripping cell, the energy reach of the analyzer is extended to 2 MeV. This analyzer has high dispersion in a first-order focus with bipolar deflection-plate voltages in the range of ±50 kV. We will present 2- and 3-D calculations of vacuum-field beam trajectories, space-charge effects, field errors, and a multipole corrector. The corrector consists of 12 rods arranged in a circle around the beam. Such a corrector has excellent properties as an electrostatic quadrupole, sextupole, or linear combination. The improved energy diagnostic allows measurements of beam charge state and energy spread, such as caused by charge exchange or temperature anisotropy, and better understanding of experimental results in longitudinal beam studies.