A S a continuation of the high-precision atomic hyperfine-structure measurements made in this laboratory in recent years, the effect of an electric field on the hyperfine-structure energy levels of Cs 133 has been examined.The increase A(< §) of the (F=4, m F =0)^(F=3 y m F = 0) transition frequency (for the ground state of Cs 133 ) has been measured in electric fields between zero and 6.7 X10 4 volts/cm by the atomic-beam magnetic-resonance technique. The transition frequency for zero electric and magnetic fields is 1 9 192 631 830=1= 10 cps. The maximum observed shift of this transition frequency caused by the electric field was approximately 4X10 3 cps. The line widths for the resonance curves obtained in these measurements were approximately 120 cps. The (4, 0)<-»(3, 0) transition was induced by using the Ramsey two-transition-region method, 2 with two microwave cavities separated by a distance L T i = 78.4 cm along the beam. The electric field was obtained with a parallel-plate condenser of length L s =66.0 cm, located between the two cavities. A crystal-stabilized klystron was used as the microwave source.

No abstract