REMEASUREMENT OF DELTAE-S IN ATOMIC HYDROGEN

The 2S122-2P322 separation ΔE-S in hydrogen has been measured by a microwave atomic-beam technique. The result obtained from four independent transitions is ΔE-S=9911.173±0.042 MHz. We combine this result with the recent determination of the Lamb shift S by Robiscoe to obtain a value for the fine-structure splitting ΔE and a value for the fine-structure constant α-1=137.0358(5). © 1969 The American Physical Society.