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arXiv · 0803.1829

Stability of the proton-to-electron mass ratio

Alexander Shelkovnikov·Robert James Butcher·Christian Chardonnet·Anne Amy-Klein
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Abstract

We report a limit on the fractional temporal variation of the proton-to-electron mass ratio as, obtained by comparing the frequency of a rovibrational transition in SF6 with the fundamental hyperfine transition in Cs. The SF6 transition was accessed using a CO2 laser to interrogate spatial 2-photon Ramsey fringes. The atomic transition was accessed using a primary standard controlled with a Cs fountain. This result is direct and model-free.

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Alexander Shelkovnikov, Robert James Butcher, Christian Chardonnet, Anne Amy-Klein. 2008-03-12. Stability of the proton-to-electron mass ratio. https://doi.org/10.1103/physrevlett.100.150801

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