Ground-state Hyperfine Transition Research Articles

Spin-Exchange Shifts in the Hydrogen Maser

Spin-exchange pulling of the $\ensuremath{\Delta}{m}_{F}=0$ ground-state hyperfine transition in atomic hydrogen is investigated for the case of self-excited oscillation on this transition in the hydrogen maser. Frequency shifts due to mistuning the maser cavity are found to compensate spin-exchange shifts so that both can be effectively eliminated. The result bears importantly on the use of the hydrogen maser as a spectroscopic tool and frequency standard and suggests a method for determining the spin-exchange shift parameter.

Stark effect on 39K hyperfine structure

The Stark shift of the ground state hyperfine transition frequency in 39K has been measured. The result is δv = -(7.60 ± 0.76) × 10 -8 E 2 cps, with E in V/cm. This result is in good agreement with a perturbation calculation.

Optical Detection of NarrowRb87Hyperfine Absorption Lines

Optical detection of the ground state hyperfine transition has been reported for sodium vapor and for cesium vapor. The collisional narrowing technique suggested by Dicke was used to reduce the Doppler width, Results are reported for Rb/sup 87/ vapor using a different optical pumping method. Absorption lines narrower, by a factor 300, than the normal Doppler width were achieved. The experimental arrangement is described. (W.D.M.)