Nuclear Magnetic Moments from the Polarization of Resonance Radiation Sodium,3S122−3P32,122

Abstract

The polarization of sodium $D$ line resonance radiation excited by plane polarized light in a magnetic field parallel to the electric vector of the exciting light increases from 16.5 percent in zero field to almost 50 percent in a field of 300 gauss as a consequence of the Paschen-Back effect of the hyperfine structure. The experimental results are well fitted by a curve calculated with $A\left(3\mathrm{}{}_{}{}^2{}_{}{}^{}P_{\frac{3}{2}}^{}{}_{}{}^{}\right)=7.45\mathrm{}\times {10}^{-4\mathrm{}}$ ${\mathrm{cm}}^{-1\mathrm{}}$ and $\tau \left(3\mathrm{}{}_{}{}^2{}_{}{}^{}P_{\frac{3}{2}}^{}{}_{}{}^{}\right)=1.64\mathrm{}\times {10}^{-8\mathrm{}}$ sec. These results are for a nuclear moment of $\frac{3}{2\left(\frac{h}{2\pi }\right)}$ which was at first thought to give too low zero field polarization (15.27 percent). The higher polarization is the effect of proximity of hyperfine levels in $3{}_{}{}^2{}_{}{}^{}P_{\frac{3}{2}}^{}{}_{}{}^{}$.