Application of graphical technique for Auger decay following photoionization of atoms

An alternative method to the density matrix formalism and based on the graphical technique of the angular momentum theory for the integration over angular and spin variables is proposed to derive the general expression for the Auger decay probability following the photoionization of polarized atoms in two-step approximation. The expression joining both steps of photoionization and Auger decay contains the possibility to investigate the polarization of all particles in the initial and final states and the angular distributions of photo-and Auger electrons. A simple way to get the expressions for special cases of the angular distribution of Auger electrons in the photoionization of randomly orientated and polarized atoms is given as an example of the practical application of the general formula. A very strong dependence of the calculated parameter of the circular magnetic dichroism in the angular distribution of Auger electrons on the final state is obtained for the transition 3p(6)4s S-2(1/2) --> 2p(-1)4s P-1(1) --> 3p(4)4s LSJ in K atoms.