Energy of the ^{229}Th Nuclear Clock Isomer Determined by Absolute γ-ray Energy Difference.

  title={Energy of the ^\{229\}Th Nuclear Clock Isomer Determined by Absolute $\gamma$-ray Energy Difference.},
  author={A. Yamaguchi and Haruka Muramatsu and T. Hayashi and N. Yuasa and K. Nakamura and Masaki Takimoto and H Haba and Kenji Konashi and M. Watanabe and Hidetoshi Kikunaga and Keisuke Maehata and Noriko Y. Yamasaki and K. Mitsuda},
  journal={Physical review letters},
  volume={123 22},
The low-lying isomeric state of ^{229}Th provides unique opportunities for high-resolution laser spectroscopy of the atomic nucleus. We determine the energy of this isomeric state by taking the absolute energy difference between the excitation energy required to populate the 29.2-keV state from the ground state and the energy emitted in its decay to the isomeric excited state. A transition-edge sensor microcalorimeter was used to measure the absolute energy of the 29.2-keV γ ray. Together with… Expand

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