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

Christian G. Parthey, Arthur Matveev, Janis Alnis +14

We have measured the 1S - 2S transition frequency in atomic hydrogen via two photon spectroscopy on a 5.8 K atomic beam. We obtain $f_{1S-2S}=2466061413187035(10)$ Hz for t…