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RESONANT OPTICAL PUMPING OF THE ISOMER 229Th WITH ENERGY 8 eV
- Authors: Karpeshin F.F.1, Trzhaskovskaya M.B2
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Affiliations:
- Mendeleev Institute for Metrology
- National Research Center “Kurchatov Institute” – Petersburg Nuclear Physics Institute
- Issue: Vol 165, No 2 (2024)
- Pages: 145-151
- Section: Articles
- URL: https://journal-vniispk.ru/0044-4510/article/view/256475
- DOI: https://doi.org/10.31857/S0044451024020019
- ID: 256475
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Abstract
The most likely candidate for the role of a nuclear optical standard is the isomer of the nuclear isotope 229mTh with an energy of 8.338 eV. The possibility to specify the value of this energy by resonant optical pumping through an electron bridge was discussed. Proper use of the natural atomic linewidths, which are many orders of magnitude larger than the natural nuclear isomeric linewidth, is critical. Recent studies have shown that broadening due to internal conversion in neutral thorium atoms leads to a gain in scan time of nine orders of magnitude, facilitating the search for electron-nuclear resonance to a feasible level. The reverse resonance conversion method proposed in this article is applicable to ionized thorium atoms. It has the potential to improve experimental efficiency by orders of magnitude. The implementation of this method requires simultaneous excitation of the nucleus and electron shell in the final state. The causal connection between this principle and the solution to the thorium riddle is shown.
About the authors
F. F. Karpeshin
Mendeleev Institute for Metrology
Email: fkarpeshin@gmail.com
Russian Federation, 190005, Saint Petersburg
M. B Trzhaskovskaya
National Research Center “Kurchatov Institute” – Petersburg Nuclear Physics Institute
Author for correspondence.
Email: fkarpeshin@gmail.com
Russian Federation, 188300 Gathcina, Leningrad region
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