The probability current density for the incident electron is given by

..........................................................................................................................(25)

and those for the four scattering processes are

.........................................................................................(26)

where, J₁, J₂, J₃, and J₄ correspond to AR, normal reflections, electron-like scattering and hole-like
scattering, respectively.

Therefore, the probabilities for the four scattering processes can be defined as A_σ(E), B_σ(E), C_σ(E), and D_σ(E),
respectively and the same can be deduced from eqn.(26), as follows;

...................................................................................(27)