Nuclear Magnetic Moments from the Polarization of Resonance Radiation Sodium,3S122−4P32,122

The polarization of sodium $3{}_{}{}^2{}_{}{}^{}S_{\frac{1}{2}}^{}{}_{}{}^{}-4\mathrm{}{}_{}{}^2{}_{}{}^{}P_{\frac{1}{2},\frac{3}{2}}^{}{}_{}{}^{}$ ($\lambda 3303\mathrm{A}$) resonance radiation excited by unpolarized light has been measured as a function of the intensity of a magnetic field applied parallel to the direction of the incident light beam. Detailed Paschen-Back effect calculations have been carried out for the hyperfine multiplet which constitutes a ${}_{}{}^2{}_{}{}^{}S_{\frac{1}{2}}^{}{}_{}{}^{}-{}_{}{}^2{}_{}{}^{}P_{\frac{3}{2}}^{}{}_{}{}^{}$ transition for a nuclear moment of $\frac{3}{2\left(\frac{h}{2\pi }\right)}$. From the fitting of the observed polarization field strength curves we find the hyperfine structure separation constant for $4{}_{}{}^2{}_{}{}^{}P_{\frac{3}{2}}^{}{}_{}{}^{}$ to be 1.87±0.05×${10}^{-4\mathrm{}}$ ${\mathrm{cm}}^{-1\mathrm{}}$. The polarization field strength curve shows very clearly the effect of proximity of hyperfine levels in $4{}_{}{}^2{}_{}{}^{}P_{\frac{3}{2}}^{}{}_{}{}^{}$.