Cesium Beam Frequency Standard Cavity Design

A new technique of constructing resonant cavities for exciting the Ramsey resonance in cesium beam frequency standards is discussed. A centrally located E-plane tee is used as the feed system in a symmetric even-order mode cavity. The location of the tee is determined initially from measurements made on the cavity when operated in a symmetric odd-order mode. Both the theoretical conditions and construction methods required to obtain very small phase differences between the oscillating magnetic fields at the ends of the cavity are described. Experimental results indicate agreement with theory and that the method is effective and simple to apply.