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arXiv · 0910.3459

Enhanced sensitivity to the fine-structure constant variation in Th IV atomic clock transition

V. V. Flambaum·S. G. Porsev
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Abstract

Our calculations have shown that the 5f_5/2-7s_1/2 23131 cm^{-1} transition from the ground state in the ion Th^{3+} is very sensitive to the temporal variation of the fine structure constant alpha (q=-75300 cm^{-1}). The line is very narrow, the ion has been trapped and laser cooled and the positive shifter line 5f_5/2-5f_7/2 4325 cm^{-1} (q=+2900 cm^{-1}) may be used as a reference. A comparison may also be made with a positive shifter in another atom or ion. This makes Th^{3+} a good candidate to search for the alpha variation.

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V. V. Flambaum, S. G. Porsev. 2009-10-19. Enhanced sensitivity to the fine-structure constant variation in Th IV atomic clock transition. https://doi.org/10.1103/physreva.80.064502

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