The polarization (relative Stokes Parameters) of the light emitted along the direction of the electron polarization is related to the shape (relative multipole moments) of the charge cloud.

Fortunately, there is a way to break the total angular momentum (J) into component parts (L,S). Since the collision is impulsive, we can relate the Stokes parameters of different transitions from the 3p4(1D) 4p manifold to the multipoles of the core and outer electron of the excited ArII ion.

Our predicted values of the multipoles of the total angular momentum of the various excited states as well as the core and excited electron (lc,lo) are given to the left.