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arXiv · 1107.3101

Improved Measurement of the Hydrogen 1S - 2S Transition Frequency

Christian G. Parthey·Arthur Matveev·Janis Alnis·Birgitta Bernhardt·Axel Beyer·Ronald Holzwarth·Aliaksei Maistrou·Randolf Pohl·Katharina Predehl·Thomas Udem·Tobias Wilken·Nikolai Kolachevsky·Michel Abgrall·Daniele Rovera·Christophe Salomon·Philippe Laurent·Theodor W. Hänsch
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Abstract

We have measured the 1S - 2S transition frequency in atomic hydrogen via two photon spectroscopy on a 5.8 K atomic beam. We obtain $f_{1S-2S} = 2 466 061 413 187 035 (10)$ Hz for the hyperfine centroid. This is a fractional frequency uncertainty of $4.2\times 10^{-15}$ improving the previous measure- ment by our own group [M. Fischer et al., Phys. Rev. Lett. 92, 230802 (2004)] by a factor of 3.3. The probe laser frequency was phase coherently linked to the mobile cesium fountain clock FOM via a frequency comb.

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Christian G. Parthey, Arthur Matveev, Janis Alnis, Birgitta Bernhardt, Axel Beyer, Ronald Holzwarth, Aliaksei Maistrou, Randolf Pohl, Katharina Predehl, Thomas Udem, Tobias Wilken, Nikolai Kolachevsky, Michel Abgrall, Daniele Rovera, Christophe Salomon, Philippe Laurent, Theodor W. Hänsch. 2011-07-15. Improved Measurement of the Hydrogen 1S - 2S Transition Frequency. https://doi.org/10.1103/physrevlett.107.203001

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