Measurement of the 2S hyperfine interval in atomic hydrogen

N Kolachevsky; A Matveev; J Alnis; C G Parthey; S G Karshenboim; T W Hänsch

doi:10.1103/PhysRevLett.102.213002

Measurement of the 2S hyperfine interval in atomic hydrogen

Phys Rev Lett. 2009 May 29;102(21):213002. doi: 10.1103/PhysRevLett.102.213002. Epub 2009 May 28.

Authors

N Kolachevsky¹, A Matveev, J Alnis, C G Parthey, S G Karshenboim, T W Hänsch

Affiliation

¹ Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany.

PMID: 19519101
DOI: 10.1103/PhysRevLett.102.213002

Abstract

An optical measurement of the 2S hyperfine interval in atomic hydrogen using two-photon spectroscopy of the 1S-2S transition gives a value of 177 556 834.3(6.7) Hz. The uncertainty is 2.4 times smaller than achieved by our group in 2003 and more than 4 times smaller than for any independent radio-frequency measurement. The specific combination of the 2S and 1S hyperfine intervals predicted by QED theory 8fHFS(2S)-fHFS(1S)=48 953(3) Hz is in good agreement with the value of 48 923(54) Hz obtained from this experiment.