The relative role of shake-up and shake-off processes in additional monopole excitation of L and M electrons due to inner atomic shell ionization

The probabilities of additional monopole excitation (shake-up) and ejection (shake-off) processes for electrons of the L and M shells upon K and L ionization for atoms with 3 ≤ Z ≤ 38 are calculated in the sudden perturbation approximation. With increasing atomic number, the portion of the nl -electron shake-offs in the total probability of monopole shake-up/shake-off processes increases from several percent in the beginning of the nl subshell population to above 50% after its filling. Within one shell, the shake-off processes are relatively more probable for electrons with smaller orbital quantum numbers.