Optical Double Resonance in Radioactive Atoms: Spin and Nuclear Moments of the Ground State ofCd109

Abstract

The optical double-resonance technique has been employed for the study of the Zeeman effect and hyperfine structure of the $\mathrm{}\left(5s5p\right)\mathrm{}{}_{}{}^3{}_{}{}^{}P_1^{}{}_{}{}^{}$ state of 470-day ${\mathrm{Cd}}^{109}$. The nuclear spin, $I$, magnetic hyperfine interaction constant, $A$, and quadrupole interaction constant, $B$, are: $I=\frac{5}{2}$, $A=-1, 148.6\pm 2.0$ Mc/sec, and $B=-167.3\mathrm{}\pm 2.0$ Mc/sec. If nuclear structure and quadrupole antishielding corrections are neglected, the corresponding nuclear moments are $\mu =-0.8286\mathrm{}\left(15\right)\mathrm{}{\mu }_N$ and $Q=+0.78\mathrm{}\left(10\right)\mathrm{}$ b. These values are discussed in terms of the configuration mixing model of Arima and Horie. A number of the problems encountered in the application of the double resonance technique to radioactive atoms are discussed. The sensitivity of the method is limited by the shot noise in the instrumentally scattered light. In the case of the present apparatus, Zeeman resonances are detectable with 2×${10}^6$ cadmium atoms in the vapor phase.