The Hyperfine Structures of Some Cadmium Lines and the Hypothesis of Nuclear spin

Measurements have been made of the hyperfine structures of the cadmium lines $\lambda \lambda 5086$, 4800, 4678, 3614, 3613, 3610, 3468, 3466, 3404, and 6438 A.U. ($2{}_{}{}^3{}_{}{}^{}P_{2,1,0}^{}{}_{}{}^{}-3{}_{}{}^3{}_{}{}^{}S_1^{}{}_{}{}^{},2\mathrm{}{}_{}{}^3{}_{}{}^{}P_2^{}{}_{}{}^{}-3{}_{}{}^3{}_{}{}^{}D_{1,2,3}^{}{}_{}{}^{},2\mathrm{}{}_{}{}^3{}_{}{}^{}P_1^{}{}_{}{}^{}-3{}_{}{}^3{}_{}{}^{}D_{1,2,3}^{}{}_{}{}^{},2\mathrm{}{}_{}{}^3{}_{}{}^{}P_0^{}{}_{}{}^{}-3{}_{}{}^3{}_{}{}^{}D_1^{}{}_{}{}^{}, \mathrm{and} 2{}_{}{}^1{}_{}{}^{}P_1^{}{}_{}{}^{}-3{}_{}{}^1{}_{}{}^{}D_2^{}{}_{}{}^{}$) using two quartz Lummer Gehrcke plates. The results are compared with those of MacNair and Schrammen, with fair agreement in general. $\lambda \lambda 3613$ and 3466 A.U. are single in agreement with Schrammen. Structure ascribed to $\lambda 3466$ A.U. by MacNair and to $\lambda 3613$ A.U. by Wali-Mohammad belongs to $\lambda \lambda 3468$ and 3614 A.U. respectively. An attempt is made to extend the application of the hypotheses of Schüler and Brück to the ${}_{}{}^3{}_{}{}^{}P-{}_{}{}^3{}_{}{}^{}D$ lines. This succeeds fairly well save in the cases of $\lambda \lambda 3466$ and 6438 both of which are single whereas if the ideas of Schüler and Brück are accepted they apparently should show readily resolvable fine structure. It is also pointed out that the hypotheses of the above authors would require incomplete polarization of the $1{}_{}{}^1{}_{}{}^{}S_0^{}{}_{}{}^{}-2{}_{}{}^3{}_{}{}^{}P_1^{}{}_{}{}^{}$ resonance line in contrast to the observed value of 100%.