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arXiv · 0804.4130

Frequency metrology on the 4s 2S1/2 - 4p 2P1/2 transition in the calcium ion for a comparison with quasar data

A. L. Wolf·S. A. van den Berg·C. Gohle·E. J. Salumbides·W. Ubachs·K. S. E. Eikema
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Abstract

High accuracy frequency metrology on the 4s 2S1/2 - 4p 2P1/2 transition in calcium ions is performed using laser cooled and crystallized ions in a linear Paul trap. Calibration is performed with a frequency comb laser, resulting in a transition frequency of f=755222766.2(1.7) MHz. The accuracy presents an improvement of more than one order of magnitude, and will facilitate a comparison with quasar data in a search for a possible change of the fine structure constant on a cosmological time scale.

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A. L. Wolf, S. A. van den Berg, C. Gohle, E. J. Salumbides, W. Ubachs, K. S. E. Eikema. 2008-04-25. Frequency metrology on the 4s 2S1/2 - 4p 2P1/2 transition in the calcium ion for a comparison with quasar data. https://doi.org/10.1103/physreva.78.032511

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