Angular Distributions of Electrons from Resonant Two-Photon Ionization of Sodium

Sodium atoms are excited to either the $3{}_{}{}^2{}_{}{}^{}P_{\frac{3}{2}}^{}{}_{}{}^{}$ or $3{}_{}{}^2{}_{}{}^{}P_{\frac{1}{2}}^{}{}_{}{}^{}$ state using a linearly polarized dye-laser beam and are subsequently ionized using a linearly polarized nitrogen-laser beam. Angular distributions of the ejected electron have been both measured and calculated for several relative orientations of the photon polarization vectors. The difference between the $s$- and $d$-continuum partial-wave phase shifts ${\delta }_s-{\delta }_d$ and the ratio of the radial dipole matrix elements ($\frac{d_s}{d_d}$) are obtained.