Keyword: plasma
Paper Title Other Keywords Page
MOC04 Commissioning Experience with CARIBU ion, background, ion-source, ECR 45
  • R.C. Vondrasek, S.I. Baker, P. Bertone, S. Caldwell, J.A. Clark, C.N. Davids, D. Lascar, A. Levand, K. Lister, R.C. Pardo, D. Peterson, D.R. Phillips, G. Savard, J.V. Schelt, M.G. Sternberg, T. Sun, B. Zabransky
    ANL, Argonne, USA
  The Californium Rare Ion Breeder Upgrade (CARIBU) of the ATLAS superconducting linac facility aims at providing low-energy and reaccelerated neutron-rich radioactive beams to address key nuclear physics and astrophysics questions. These beams are obtained from fission fragments of a Cf-252 source, thermalized and collected into a low-energy particle beam by a helium gas catcher, mass analyzed by an isobar separator, and charge bred with an ECR ion source to higher charge states for acceleration in ATLAS. Low-energy mass separated radioactive beams have been extracted, charge bred with a 10% efficiency, reaccelerated to 6 MeV/u, and delivered to GAMMASPHERE for beta decay studies. In addition, the Canadian Penning Trap (CPT) mass spectrometer has been relocated to the CARIBU low-energy beam line. Mass measurements on over 42 neutron rich nuclei have already been performed and additional measurements are underway. In addition, a new tape station for beta decay studies has just been commissioned. In this talk I will describe the current status of the overall CARIBU system and the plans for bringing the system into full operation and use in research with accelerated beams.  
slides icon Slides MOC04 [3.744 MB]  
TUC01 Physical Design of the SPES Facility rfq, target, ion, linac 136
  • M. Comunian
    INFN/LNL, Legnaro (PD), Italy
  SPES (Selective Production of Exotic Species) is the Italian project for a radioactive ion beam (RIB) facility based on a cyclotron as primary accelerator and on the existing superconducting linac ALPI as post accelerator. The cyclotron, energy up to 70 MeV and total current of 0.75 mA, shared on two exits, is in construction in the industry. The production of neutron-rich radioactive nuclei, with ISOL technique, employs the proton induced fission on a direct target of UCx; the fission rate expected with a proton beam of 40 MeV and 0.2 mA, is 1013 fissions/s. The main goal of physical design of the SPES facility is to provide an accelerator system to perform forefront research in nuclear physics by studying nuclei far from stability, in particular neutron-rich radioactive nuclei with masses in the range of 80–160. The final RIB energy on the experimental target will be up to 11 MeV/A for A = 130, with an intensity in the range of 107–109 pps.  
slides icon Slides TUC01 [5.313 MB]  
TUC03 Laser Ablation of Solids into an Electron Cyclotron Resonance Ion Sources for Accelerator Mass Spectroscopy laser, ion, ECR, target 149
  • T. Palchan, F.G. Kondev, S.A. Kondrashev, C. Nair, R.C. Pardo, R.H. Scott, R.C. Vondrasek
    ANL, Argonne, USA
  • W. Bauder, P. Collon
    University of Notre Dame, Indiana, USA
  • J.F. Berg, T. Maddock, G. Palmotti, G. Youinou
    INL, Idaho Falls, Idaho, USA
  • G. Imel
    ISU, Pocatello, Idaho, USA
  • M. Paul
    The Hebrew University of Jerusalem, The Racah Institute of Physics, Jerusalem, Israel
  • M. Salvatores
    CEA Cadarache, Saint Paul Lez Durance, France
  Funding: This work is supported by the U.S. Department of Energy, Office of Nuclear Physics, under contract No. DE-AC02-06CH11357.
A project using accelerator mass spectrometry (AMS) is underway at the ATLAS facility to measure the atom densities of transmutation products present in samples irradiated in the Advanced Test Reactor at INL. These atom densities will be used to infer effective actinide neutron capture cross-sections ranging from Thorium to Califorium isotopes in different neutron spectra relevant to advanced fuel cycles. This project will require the measurement of many samples with high precision and accuracy. The AMS technique at ATLAS is based on production of highly-charged positive ions in an ECRIS followed by injection into a linear accelerator. We use a picosecond laser to ablate the actinide material into the ion source. We expect that the laser ablation technique will have higher efficiency and lower chamber contamination than sputtering or oven evaporation thus reducing ‘cross talk’ between samples. In addition a multi-sample holder/changer is part of the project to allow for a quick change between multiple samples. The results of off-line ablation tests and first results of a beam generated by the laser coupled to the ECR will be discussed as well as the overall project schedule.
slides icon Slides TUC03 [1.610 MB]  
WEA02 Focusing of Intense Heavy Ion Beams with Plasma Lenses electron, focusing, ion, heavy-ion 163
  • O. Meusel, M. Droba, U. Ratzinger, K. Schulte
    IAP, Frankfurt am Main, Germany
  Gabor lenses are a special type of plasma lens using a stable confined electron cloud for beam focusing. The electrons provide space charge neutralization of the beam traveling through the lens volume. At the same time a radial symmetric electrostatic self field focuses the beam mass independently. It is possible to control the density and distribution of the confined electrons providing variable focusing strength and moderate emittance growth of the beam. The knowledge of the behavior of the electron column inside this lens type is essential to understand the impact on beam transport. Therefore several diagnostic tools were developed to measure the electron cloud properties with and without ion beam propagation through Gabor lenses. Based on experimental results a new Gabor plasma lens has been designed for focusing heavy ion beams. A comparison of this lens type and a superconducting solenoid is planned at the low energy transport section of the GSI - High Current Test Injector (HOSTI).  
slides icon Slides WEA02 [1.572 MB]  
WEB05 ECRIS Latest Developments ion, electron, ECRIS, ion-source 173
  • L. Celona, G. Castro, S. Gammino, D. Mascali
    INFN/LNS, Catania, Italy
  • G. Ciavola
    CNAO Foundation, Milan, Italy
  The production of intense beams of highly charged ions (HCI) is one of the most relevant challenge for the future accelerator facilities. Electron Cyclotron Resonance Ion Sources (ECRIS) are nowadays the most powerful devices able to feed accelerators with HCI in a reliable and efficient way. The reliability of frontier solutions for magnets and the increased costs for microwave generators make scaling to larger frequency not viable. Any further improvement of ECRIS output currents and average charge state requires a deep understanding of electron and ion dynamics in the plasma. In the past 20 years different teams have been working in the forefront of ion source developments with both experimental and theoretical activities, proposing different solutions to improve the production rate. The paper will discuss the most recent technological developments in the field, worldwide, together with the modeling issues of non-classical evidences like sensitivity of Electron Energy Distribution Function to the magnetic field detuning, influence of plasma turbulences on electron heating and ion confinement, coupling between electron and ion dynamics and relative impact on the formed ion beam.