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Beene, J.R.

Paper Title Page
TPPE019 Laser Ion Source Development for ISOL Systems at RIA 1640
 
  • Y. Liu, C. Baktash, J.R. Beene, H. Z. Bilheux, C.C. Havener, H.F. Krause, D.R. Schultz, D.W. Stracener, C.R. Vane
    ORNL, Oak Ridge, Tennessee
  • K. Brueck, Ch. Geppert, T. Kessler, K. Wendt
    Johannes Gutenberg University Mainz, Mainz
 
  Funding: Managed by UT-Battelle, LLC, for the U.S. DOE under contract DE-AC05-00OR22725.

The isobaric purity of radioactive ion beams (RIBs) is of crucial importance to many experiments. Laser ion sources based on resonant photoionization have already proved to be of great value at existing ISOL RIB facilities. In these ion sources, ions of a selected isotope are produced by laser radiation via stepwise atomic resonant excitations followed by ionization in the last transition. Because each element has its own unique atomic energy levels, the resonant photoionization process can provide elemental selectivity of nearly 100%. We have initiated a research effort to develop a prototype laser ion source with the potential to achieve the high selectivity and high efficiency required for research with ISOL-generated RIBs at the Rare Isotope Accelerator (RIA). A pilot experiment has been conducted to demonstrate resonant photoionization of three atomic species using all-solid-state tunable Ti:Sapphire lasers. Three Ti:Sapphire lasers were provided by the University of Mainz and used in the experiment for three-photon resonant ionization of the elements. Laser generated Sn, Ni, and Ge ions have been successfully obtained in a hot-cavity laser ion source with overall efficiencies of 22%, 2.7%, and 3.3%, respectively.

 
TPPE020 Radioactive Ion Beam Development at the Holifield Radioactive Ion Beam Facility
 
  • D.W. Stracener, G. Alton, J.R. Beene, H. Z. Bilheux, J.-C. Bilheux, J.C. Blackmon, D. Dowling, R.C. Juras, Y. Kawai, Y. Liu, M.J. Meigs, P.E. Mueller, B. A. T. Tatum
    ORNL, Oak Ridge, Tennessee
  • H.K. Carter, A. Kronenberg, E.H. Spejewski
    Center of Excellence for RIB Studies for Stewardship Science, Oak Ridge Associated Universities, Oak Ridge, Tennessee
 
  Funding: Managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725.

Radioactive beams are produced at the Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory using the Isotope Separator On-Line (ISOL) technique. Radioactive nuclei are produced in a thick target via irradiation with energetic light ions (protons, deuterons, helium isotopes) and then post-accelerated to a few MeV/nucleon for use in nuclear physics experiments. An overview of radioactive beam development at the HRIBF will be presented, including ion source development, improvements in the ISOL production targets, and a description of techniques to improve the quality (intensity and purity) of the beams. Facilities for radioactive ion beam development include two ion source test facilities, a target/ion source preparation and quality assurance facility, and an in-beam test facility where low intensity production beams are used. A new test facility, the High Power Target Laboratory, will be available later this year. At this facility, high intensity production beams will be available to measure the power-handling capabilities of ISOL production targets. This information will be used to optimize target materials and geometries for high power densities.

 
RPPT062 Radiation Simulations for the Proposed ISOL Stations for RIA 3561
 
  • R.M. Ronningen, V. Blideanu, G. Bollen, D. Lawton, P.F. Mantica, D.J. Morrissey, B. Sherrill, A. Zeller
    NSCL, East Lansing, Michigan
  • L. Ahle, J.L. Boles, S. Reyes, W. Stein
    LLNL, Livermore, California
  • J.R. Beene, W. Burgess, H.K. Carter, D.L. Conner, T.A. Gabriel, L.K. Mansur, R. Remec, M.J. Rennich, D.W. Stracener, M. Wendel
    ORNL, Oak Ridge, Tennessee
  • T.A. Bredeweg, F.M. Nortier, D.J. Vieira
    LANL, Los Alamos, New Mexico
  • P. Bricault
    TRIUMF, Vancouver
  • L.H. Heilbronn
    LBNL, Berkeley, California
 
  Funding: This work is supported in part by Michigan State University, the U.S. Department of Energy, and the National Research Council of Canada.

The Department of Energy's Office of Nuclear Physics, within the Office of Science (SC), has given high priority to consider and analyze design concepts for the target areas for the production of rare isotopes via the ISOL technique at the Rare-Isotope Accelerator (RIA) Facility. Key criteria are the maximum primary beam power of 400 kW, minimizing target change-out time, good radiological protection, flexibility with respect to implementing new target concepts, and the analysis and minimization of hazards associated with the operation of the facility. We will present examples of on-going work on simulations of radiation heating of targets, surrounding components and shielding, component activation, and levels of radiation dose, using the simulation codes MARS, MCNPX, and PHITS. These results are important to make decisions that may have a major impact on the layout, operational efficiency and cost of the facility, hazard analysis, shielding design, civil construction, component design, and material selection, overall layout, and remote handling concepts.

 
RPPT063 Radiation Simulations and Development of Concepts for High Power Beam Dumps, Catchers and Pre-separator Area Layouts for the Fragment Separators for RIA 3594
 
  • R.M. Ronningen, V. Blideanu, G. Bollen, D. Lawton, D.J. Morrissey, B. Sherrill, A. Zeller
    NSCL, East Lansing, Michigan
  • L. Ahle, J.L. Boles, S. Reyes, W. Stein, A. Stoyer
    LLNL, Livermore, California
  • J.R. Beene, W. Burgess, H.K. Carter, D.L. Conner, T.A. Gabriel, L.K. Mansur, R. Remec, M.J. Rennich, D.W. Stracener, M. Wendel
    ORNL, Oak Ridge, Tennessee
  • H. Geissel, H. Iwase
    GSI, Darmstadt
  • I.C. Gomes, F. Levand, Y. Momozaki, J.A. Nolen, B. Reed
    ANL, Argonne, Illinois
  • L.H. Heilbronn
    LBNL, Berkeley, California
 
  Funding: This work is supported in part by Michigan State University, the US DOE, and the Gesellschaft für Schwerionenforschung, Germany.

The development of high-power beam dumps and catchers, and pre-separator layouts for proposed fragment separators of the Rare-Isotope Accelerator (RIA) facility are important in realizing how to handle the 400 kW in the primary beam. We will present examples of pre-conceptual designs of beam dumps, fragment catchers, and the pre-separator layout. We will also present examples of ongoing work on radiation simulations using the heavy-ion-transport code PHITS, characterizing the secondary radiation produced by the high-power ion beams interacting with these devices. Results on radiation heating of targets, magnet coils, associated hardware and shielding, component activation, and levels of radiation dose will be presented. These initial studies will yield insight into the impact of the high-power dissipation on fragment separator design, remote handling concepts, nuclear safety and potential facility hazard classification, shielding design, civil construction design, component design, and material choices. Furthermore, they will provide guidance on detailed radiation analyses as designs mature.

 
RPPT064 Holifield Radioactive Ion Beam Facility Development and Status 3641
 
  • A. Tatum, J.R. Beene
    ORNL, Oak Ridge, Tennessee
 
  Funding: Managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725.

The Holifield Radioactive Ion Beam Facility (HRIBF) is a national user facility dedicated to nuclear structure, reactions, and nuclear astrophysics research with radioactive ion beams (RIBs) using the isotope separator on-line (ISOL) technique. An integrated strategic plan for physics, experimental systems, and RIB production facilities have been developed and implementation of the plan is under way. Specific research objectives are defined for studying the nature of nucleonic matter, the origin of elements, solar physics, and synthesis of heavy elements. Experimental systems upgrade plans include new detector arrays and beam lines, and expansion and upgrade of existing devices. A multifaceted facility expansion plan includes a $4.75M High Power Target Laboratory (HPTL), presently under construction, to provide a facility for testing new target materials, target geometries, ion sources, and beam preparation techniques. Additional planned upgrades include a second RIB production system (IRIS2), an external axial injection system for the present driver cyclotron, ORIC, and an additional driver accelerator for producing high-intensity neutron-rich beams.

 
FPAE053 Isobar Suppression by Photodetachment in a Gas-Filled RF Quadrupole Ion Guide 3250
 
  • Y. Liu, J.R. Beene, C.C. Havener, J. F. Liang
    ORNL, Oak Ridge, Tennessee
  • A.C. Havener
    University of Tennessee, Knoxville, Tennessee
 
  Funding: Managed by UT-Battelle, LLC, for the U.S. DOE under contract DE-AC05-00OR22725. Co-author Aaron Havener was under a U.S. DOE Science Undergraduate Laboratory Internship.

A novel method is described for selective suppression of isobar contaminants in negative radioactive ion beams. Negative ion beams extracted from an ion source were decelerated to low energies and injected into a gas-filled radio-frequency quadrupole (RFQ) ion guide where the ions were cooled and unwanted ions were selectively removed by non-resonant photodetachment with photons of sufficient energy. Simulation studies show that the laser-ion interaction time in a 40 cm long RFQ ion guide can be on the order of milliseconds, thus, high efficiency photodetachment is possible with commercially available CW lasers. There are a number of adjacent-Z species whose negative ions are such that photodetachment can be used to suppress the unwanted negative ion species while leaving the species of interest intact. Examples of particular interest include suppressing the 56Co- component in a mixed 56Ni- + 56Co- beam and the 17O- component in a mixed 17O- + 17F- beam. In a proof–of-principle experiment a CW Nd:YAG laser at 1064 nm wavelength was used to selectively remove Co- ions in the (Ni, Co) pair. With laser power on the order of 3 W, 95% of Co- beams were suppressed while only 10% of Ni- beams were neutralized in a He-filled RFQ guide.