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New Limits to the Drift of Fundamental Constants from Laboratory Measurements

M. Fischer·N. Kolachevsky·M. Zimmermann·R. Holzwarth·Th. Udem·T. W. Haensch·M. Abgrall·J. Gruenert·I. Maksimovic·S. Bize·H. Marion·F. Pereira Dos Santos·P. Lemonde·G. Santarelli·P. Laurent·A. Clairon·C. Salomon·M. Haas·U. D. Jentschura·C. H. Keitel
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Abstract

We have remeasured the absolute $1S$-$2S$ transition frequency $ν_{\rm {H}}$ in atomic hydrogen. A comparison with the result of the previous measurement performed in 1999 sets a limit of $(-29\pm 57)$ Hz for the drift of $ν_{\rm {H}}$ with respect to the ground state hyperfine splitting $ν_{\rm {Cs}}$ in $^{133}$Cs. Combining this result with the recently published optical transition frequency in $^{199}$Hg$^+$ against $ν_{\rm {Cs}}$ and a microwave $^{87}$Rb and $^{133}$Cs clock comparison, we deduce separate limits on $\dotα/α= (-0.9\pm 2.9)\times 10^{-15}$ yr$^{-1}$ and the fractional time variation of the ratio of Rb and Cs nuclear magnetic moments $μ_{\rm {Rb}}/μ_{\rm {Cs}}$ equal to $(-0.5 \pm 1.7)\times 10^{-15}$ yr$^{-1}$. The latter provides information on the temporal behavior of the constant of strong interaction.

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M. Fischer, N. Kolachevsky, M. Zimmermann, R. Holzwarth, Th. Udem, T. W. Haensch, M. Abgrall, J. Gruenert, I. Maksimovic, S. Bize, H. Marion, F. Pereira Dos Santos, P. Lemonde, G. Santarelli, P. Laurent, A. Clairon, C. Salomon, M. Haas, U. D. Jentschura, C. H. Keitel. 2004-06-04. New Limits to the Drift of Fundamental Constants from Laboratory Measurements. https://doi.org/10.1103/physrevlett.92.230802

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