Azimuthal asymmetry in elastic electron scattering by polarized 3P sodium atoms

Azimuthal asymmetry of the differential cross sections between two polarized states has been measured in elastic electron scattering by laser-excited sodium atoms prepared in the 32P3/2,F=3 (MF=+3 or MF=-3) polarized state. These results are an observation of the orbital effect in the elastic electron collision due to ML atomic state perpendicular to the scattering plane. Data are reported for electron energies in the range of 1 endash 10 eV, comparable with the kinetic energy of the atomic valence electron. At polar scattering angle θ=135 degree we found the asymmetry to be more significant when the incident electron energy is lower. Differential cross sections of these excited, polarized states were obtained at 135 degree as a function of electron energy as well. The experimental results are compared with R-matrix-based close coupling, and convergent-close-coupling calculations. copyright 1996 The American Physical Society