P13-Orientation Velocity-Changing Collision Kernels Studied by Isolated Multipole Echoes

We report studies of ${}_{}{}^{174}{}_{}{}^{}\mathrm{Yb}$ ${}_{}{}^3{}_{}{}^{}P_1^{}{}_{}{}^{}$-orientation velocity-changing kernels with resolution sufficient to observe both classical and wave mechanical features. The measurements employ photon-echo techniques in which the echo intensity depends on the square of an isolated $J=1\mathrm{}$ multipole moment for which the velocity-changing kernel is diagonal.