Measurement of the2S122−2P322Interval in Atomic Hydrogen

Abstract

The $2{}_{}{}^2{}_{}{}^{}S_{\frac{1}{2}}^{}{}_{}{}^{}-2{}_{}{}^2{}_{}{}^{}P_{\frac{3}{2}}^{}{}_{}{}^{}$ interval has been determined to be 9911.38(3) MHz in atomic hydrogen, by using the rf electric dipole transitions $\alpha a$ and $\alpha b$. Combining this result with the current experimental values of the $2{}_{}{}^2{}_{}{}^{}S_{\frac{1}{2}}^{}{}_{}{}^{}-2{}_{}{}^2{}_{}{}^{}P_{\frac{1}{2}}^{}{}_{}{}^{}$ interval, we obtain $\Delta E_{\mathrm{H}}=10969.20\mathrm{}\left(6\right)\mathrm{}$ MHz. The corresponding value for ${\alpha }^{-1\mathrm{}}$ is 137.0350(4).