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Testing the time dependence of the fundamental constants in the spectra of multicharged ions

O. Yu. Andreev·L. N. Labzowsky·G. Plunien·G. Soff
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Abstract

A new method for measuring a possible time dependence of the fine-structure constant ($α$) is proposed. The method is based on the level-crossing in two-electron highly-charged ions facilitating resonance laser measurements of the distance between the levels at the point of crossing. This provides an enhancement factor of about $10^{3}$ in Helium-like Europium and thus reduces the requirements for the relative accuracy of resonance laser measurements at about $10^{-12}$.

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O. Yu. Andreev, L. N. Labzowsky, G. Plunien, G. Soff. 2005-05-11. Testing the time dependence of the fundamental constants in the spectra of multicharged ions. https://doi.org/10.1103/physrevlett.94.243002

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