The accuracy of the hydrogen 1S-2S measurement was mainly limited by the second-order Doppler shift of the moving atoms (and to a lesser degree the AC Stark shift of the excitation laser and the 2S-4P quench light). The comparison between the laser frequency and the Cesium fountain clock was done with an optical frequency comb which introduces a negligible uncertainty (< 1E-19).
Isn't it fun to get your own field of expertise (wrongly) explained to you on the internet?
Edit: I never said that it is easy to derive the corrections listed in the CODATA paper. However, it is relatively easy to calculate them.
Isn't it fun to get your own field of expertise (wrongly) explained to you on the internet?
Edit: I never said that it is easy to derive the corrections listed in the CODATA paper. However, it is relatively easy to calculate them.