Lifetime Measurement of the ^{229}Th Nuclear Isomer.

  title={Lifetime Measurement of the ^\{229\}Th Nuclear Isomer.},
  author={Benedict Seiferle and Lars C. von der Wense and Peter G. Thirolf},
  journal={Physical review letters},
  volume={118 4},
The first excited isomeric state of ^{229}Th possesses the lowest energy among all known excited nuclear states. The expected energy is accessible with today's laser technology and in principle allows for a direct optical laser excitation of the nucleus. The isomer decays via three channels to its ground state (internal conversion, γ decay, and bound internal conversion), whose strengths depend on the charge state of ^{229m}Th. We report on the measurement of the internal-conversion decay half… 

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Phd by thesis
  • R. Lathe
  • Geography, Environmental Science
  • 1988
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  • Instrum. Methods Phys. Res., Sect. A 735, 229
  • 2014
  • Phys. JETP 72,
  • 1991
  • Rev. C 49, 1845
  • 1994
  • Rev. Lett. 64, 271
  • 1990
Nature Phys
  • 10, 933-936
  • 2014
  • Bur. Stand. (U.S.), Monogr. 145
  • 1975