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^ Dimarcq, Noel; Gertsvolf, Marina; Mileti, Gaetano; Bize, Sebastien; Oates, Christopher; Peik, Ekkehard; Calonico, Davide; Ido, Tetsuya; Tavella, Patrizia; Meynadier, Frédéric (2024). "Roadmap towards the redefinition of the second". Metrologia. 61 (1): 012001. arXiv:2307.14141. Bibcode:2024Metro..61a2001D. doi:10.1088/1681-7575/ad17d2.

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Ludlow, A. D.; Boyd, M. M.; Ye, Jun; Peik, E.; Schmidt, P. O. (26 June 2015). "Optical atomic clocks". Reviews of Modern Physics. 87 (2): 637–701. arXiv:1407.3493. Bibcode:2015RvMP...87..637L. doi:10.1103/RevModPhys.87.637. S2CID 119116973.

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^
Seiferle, Benedict; von der Wense, Lars; Thirolf, Peter G. (2017). "Lifetime measurement of the 229Th nuclear isomer". Physical Review Letters. 118 (4) 042501. arXiv:1801.05205. Bibcode:2017PhRvL.118d2501S. doi:10.1103/PhysRevLett.118.042501. PMID 28186791. S2CID 37518294. A half-life of 7±1 μs has been measured

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Tiedau, J.; Okhapkin, M. V.; Zhang, K.; Thielking, J.; Zitzer, G.; Peik, E.; et al. (29 April 2024). "Laser Excitation of the Th-229 Nucleus" (PDF). Physical Review Letters. 132 (18) 182501. Bibcode:2024PhRvL.132r2501T. doi:10.1103/PhysRevLett.132.182501. PMID 38759160. The nuclear resonance for the Th4+ ions in Th:CaF2 is measured at the wavelength 148.3821(5) nm, frequency 2020.409(7) THz, and the fluorescence lifetime in the crystal is 630(15) s, corresponding to an isomer half-life of 1740(50) s for a nucleus isolated in vacuum.

^
von der Wense, Lars; Seiferle, Benedict; Laatiaoui, Mustapha; Neumayr, Jürgen B.; Maier, Hans-Jörg; Wirth, Hans-Friedrich; Mokry, Christoph; Runke, Jörg; Eberhardt, Klaus; Düllmann, Christoph E.; Trautmann, Norbert G.; Thirolf, Peter G. (5 May 2016). "Direct detection of the 229Th nuclear clock transition". Nature. 533 (7601): 47–51. arXiv:1710.11398. Bibcode:2016Natur.533...47V. doi:10.1038/nature17669. PMID 27147026. S2CID 205248786.

^ Thielking, J.; Okhapkin, M.V.; Glowacki, P.; Meier, D.M.; von der Wense, L.; Seiferle, B.; Düllmann, C.E.; Thirolf, P.G.; Peik, E. (2018). "Laser spectroscopic characterization of the nuclear-clock isomer 229mTh". Nature. 556 (7701): 321–325. arXiv:1709.05325. Bibcode:2018Natur.556..321T. doi:10.1038/s41586-018-0011-8. PMID 29670266. S2CID 4990345.

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^
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Thirolf, Peter (29 April 2024). "Shedding Light on the Thorium-229 Nuclear Clock Isomer". Physics. Vol. 17. doi:10.1103/Physics.17.71.

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Elwell, R.; Schneider, Christian; Jeet, Justin; Terhune, J. E. S.; Morgan, H. W. T.; Alexandrova, A. N.; Tran Tan, Hoang Bao; Derevianko, Andrei; Hudson, Eric R. (2 July 2024). "Laser excitation of the 229Th nuclear isomeric transition in a solid-state host". Physical Review Letters. 133 (1) 013201. arXiv:2404.12311. doi:10.1103/PhysRevLett.133.013201. PMID 39042795. a narrow, laser-linewidth-limited spectral feature at 148.38219(4)stat(20)sys nm (2,020,407.3(5)stat(30)sys GHz) that decays with a lifetime of 568(13)stat(20)sys s. This feature is assigned to the excitation of the 229Th nuclear isomeric state, whose energy is found to be 8.355733(2)stat(10) eV in 229Th:LiSrAlF6.

^
Zhang, Chuankun; Ooi, Tian; Higgins, Jacob S.; Doyle, Jack F.; von der Wense, Lars; Beeks, Kjeld; Leitner, Adrian; Kazakov, Georgy; Li, Peng; Thirolf, Peter G.; Schumm, Thorsten; Ye, Jun (4 September 2024). "Frequency ratio of the 229mTh nuclear isomeric transition and the 87Sr atomic clock". Nature. 633 (8028): 63–70. arXiv:2406.18719. Bibcode:2024Natur.633...63Z. doi:10.1038/s41586-024-07839-6. PMID 39232152. The transition frequency between the I = 5/2 ground state and the I = 3/2 excited state is determined as: 𝜈Th = ⁠1/6⁠ (𝜈a + 2𝜈b + 2𝜈c + 𝜈d) = 2020407384335(2) kHz.

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  MD5:      ddcc270f6b749d13f1d6ad1887c81cd4

�� INTEGRITY HASHES:
  SHA-256:  63d818be2f49d53672a868d73b83c937a22126047ef87fb10964fe015d71111c
  BLAKE2b:  1ffcfdf5254e2096d0afcf032a8a5aee3d59bba1a5fb72a64bef10aa0ff7f939
  MD5:      a328f8a8a74dbd03ef3831da3754384c

@mes: ^ Dimarcq, Noel; | Ecency