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arXiv · 1801.08816

New measurement of the $1S-3S$ transition frequency of hydrogen: contribution to the proton charge radius puzzle

Hélène Fleurbaey·Sandrine Galtier·Simon Thomas·Marie Bonnaud·Lucile Julien·François Biraben·François Nez·Michel Abgrall·Jocelyne Guéna
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Abstract

We present a new measurement of the $1S-3S$ two-photon transition frequency of hydrogen, realized with a continuous-wave excitation laser at 205 nm on a room-temperature atomic beam, with a relative uncertainty of $9\times10^{-13}$. The proton charge radius deduced from this measurement, $r_\text{p}=0.877(13)$ fm, is in very good agreement with the current CODATA-recommended value. This result contributes to the ongoing search to solve the proton charge radius puzzle, which arose from a discrepancy between the CODATA value and a more precise determination of $r_\text{p}$ from muonic hydrogen spectroscopy.

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Hélène Fleurbaey, Sandrine Galtier, Simon Thomas, Marie Bonnaud, Lucile Julien, François Biraben, François Nez, Michel Abgrall, Jocelyne Guéna. 2018-01-26. New measurement of the $1S-3S$ transition frequency of hydrogen: contribution to the proton charge radius puzzle. https://doi.org/10.1103/physrevlett.120.183001

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