Hyperfine Interactions

, Volume 162, Issue 1–4, pp 115–123 | Cite as

Pumping 229m Th by Hollow-Cathode Discharge

  • T. T. Inamura
  • T. Mitsugashira
  • THE Oarai Collaboration


An extremely low-lying nuclear isomer in 229Th is still to be established in spite of efforts made since the first postulation of the isomer in 1976. To study such an extremely low-lying nuclear isomer, we have built an entirely new device that is based on the well-established atomic spectroscopic technique: Hollow-cathode discharge. The isomer in question is expected to be populated by the process NEET through atomic excited states if it exists in an energy range of electron volt. After switching off the discharge, we will measure alphas from the isomer, photons from the isomer itself and photons from atomic states to which the isomer is expected to decay by the inverse NEET. Our experiment is under way at Oarai using the world's radiochemically purest 229Th sample.

Key Words

alphas and photons NEET by electric discharge 


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Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • T. T. Inamura
    • 1
  • T. Mitsugashira
    • 2
  • THE Oarai Collaboration
  1. 1.Accelerator Research FacilityRIKENWako-shiJapan
  2. 2.Oarai branch, Institute for Materials ResearchTohoku UniversityOarai-machiJapan

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