Searching for the Decay and Half Life of the 7.6 eV Excited State in the Thorium-229 Nucleus

ORAL

Abstract

Thorium-229 has the lowest known nuclear excited state at 7.6 eV [1]. The state has been known to exist for 35 years, but it's decay to the ground state has never been directly observed. Because it has an extremely low energy for a nuclear state, a unique set of applications are possible, including a nuclear clock, a nuclear laser, and investigations into Bound Internal Conversion, Nuclear Excitation by Electronic Transition and Nuclear Excitation by Electron Capture. We are currently conducting experiments to observe the decay and measure it's half life. We use uranium-233 alpha decay as our source of thorium-229 excited nuclei and use several different methods to search for the half life over a range from nanoseconds to days.\\[4pt] [1] Beck et al., PRL 98, 142501 (2007)

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Authors

  • Erik Swanberg

    UC Berkeley

  • G.V. Brown

    Department of Physics at CSU, Fresno, Lawrence Livermore National Laboratory, Stanford University, Advanced Light Source, Lawrence Berkeley National Lab, Nanoelectronics Research Institute, Japan Atomic Energy Agency, University of Tokyo, Cornell University, Tokyo Institute of Technology, Suranaree University of Technology, Shandong University, Stanford Synchrotron Radiation Lightsource, UC Davis, CSU Dominguez Hills, Thomas Jefferson National Accelerator Facility, UC Berkeley, ANL, UChicago/ANL, UManitoba, Northwestern U/ANL, LLNL, UCB/LLNL, McGill U, McGill U/ANL, University of Nevada, Reno, Hitachi Global Storage Technology, Advanced Light Source, Stanford Synchrotron Radiation Laboratory, Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Materials Science and Engineering, Stanford University, Radiation Oncology, Stanford University School of Medicine, Missouri University of Science and Technology, International Institute of Physics, University of Missouri, University of Notre Dame du Lac, Department of Physics, California State University, Fresno, California, California State University Long Beach, BNL, IWF Dresden, Department of Physics, University of California, Davis, CA 95616, USA, University of California, Merced, Laboratoire Univers et Particules de Montpellier, IN2P3 (France), SLAC National Accelerator Laboratory/Stanford University/KIPAC, University of Perugia, University of Washington, CEA/Saclay, UNR, UNM, UCSD, RAL, ILE, MIT, LANL, LLE, NRL, SLAC National Accelerator Laboratory, Technische Universitaet Berlin, Max Born Institut, Hiroshima University, Western Michigan University, MPIK

  • G.V. Brown

    Department of Physics at CSU, Fresno, Lawrence Livermore National Laboratory, Stanford University, Advanced Light Source, Lawrence Berkeley National Lab, Nanoelectronics Research Institute, Japan Atomic Energy Agency, University of Tokyo, Cornell University, Tokyo Institute of Technology, Suranaree University of Technology, Shandong University, Stanford Synchrotron Radiation Lightsource, UC Davis, CSU Dominguez Hills, Thomas Jefferson National Accelerator Facility, UC Berkeley, ANL, UChicago/ANL, UManitoba, Northwestern U/ANL, LLNL, UCB/LLNL, McGill U, McGill U/ANL, University of Nevada, Reno, Hitachi Global Storage Technology, Advanced Light Source, Stanford Synchrotron Radiation Laboratory, Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Materials Science and Engineering, Stanford University, Radiation Oncology, Stanford University School of Medicine, Missouri University of Science and Technology, International Institute of Physics, University of Missouri, University of Notre Dame du Lac, Department of Physics, California State University, Fresno, California, California State University Long Beach, BNL, IWF Dresden, Department of Physics, University of California, Davis, CA 95616, USA, University of California, Merced, Laboratoire Univers et Particules de Montpellier, IN2P3 (France), SLAC National Accelerator Laboratory/Stanford University/KIPAC, University of Perugia, University of Washington, CEA/Saclay, UNR, UNM, UCSD, RAL, ILE, MIT, LANL, LLE, NRL, SLAC National Accelerator Laboratory, Technische Universitaet Berlin, Max Born Institut, Hiroshima University, Western Michigan University, MPIK

  • G.V. Brown

    Department of Physics at CSU, Fresno, Lawrence Livermore National Laboratory, Stanford University, Advanced Light Source, Lawrence Berkeley National Lab, Nanoelectronics Research Institute, Japan Atomic Energy Agency, University of Tokyo, Cornell University, Tokyo Institute of Technology, Suranaree University of Technology, Shandong University, Stanford Synchrotron Radiation Lightsource, UC Davis, CSU Dominguez Hills, Thomas Jefferson National Accelerator Facility, UC Berkeley, ANL, UChicago/ANL, UManitoba, Northwestern U/ANL, LLNL, UCB/LLNL, McGill U, McGill U/ANL, University of Nevada, Reno, Hitachi Global Storage Technology, Advanced Light Source, Stanford Synchrotron Radiation Laboratory, Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Materials Science and Engineering, Stanford University, Radiation Oncology, Stanford University School of Medicine, Missouri University of Science and Technology, International Institute of Physics, University of Missouri, University of Notre Dame du Lac, Department of Physics, California State University, Fresno, California, California State University Long Beach, BNL, IWF Dresden, Department of Physics, University of California, Davis, CA 95616, USA, University of California, Merced, Laboratoire Univers et Particules de Montpellier, IN2P3 (France), SLAC National Accelerator Laboratory/Stanford University/KIPAC, University of Perugia, University of Washington, CEA/Saclay, UNR, UNM, UCSD, RAL, ILE, MIT, LANL, LLE, NRL, SLAC National Accelerator Laboratory, Technische Universitaet Berlin, Max Born Institut, Hiroshima University, Western Michigan University, MPIK