THE EGS5 CODE SYSTEM

Table 2.9: Formulas used in various simulation modes employing detailed treatment of Compton
and Rayleigh scattering.
Equation Simulation mode
2.430 Compton scattering with LP, σ bC , S(x, Z) and DB.
2.431 Compton scattering with LP.
2.432 Rayleigh scattering with LP.
2.415 Compton scattering with σ bC , S(x, Z) and DB.
2.425 Compton scattering with σ bC and S(x, Z).
2.426 Compton scattering with σ bC .
1. Casnati [43, 44]
2. Kolbenstvedt-revised [105]
3. Kolbenstvedt-original [92]
4. Jakoby [80]
5. Gryziński [65] Equation 21
6. Gryziński-relativistic [65] Equation 23
EII is treated as a subset of Møller scattering in EGS, so neither the electron mean-free path nor
the stopping power are modified when EII is treated. Molecular binding effects are ignored, and
electron impact ionization in L and higher shells is treated as free electron Møller scattering.
The ratio of the K-shell EII cross section of J-th element in a material to the Møller scattering
cross section is calculated by the following equation:
R(E, J) =
∑ Jj=1
Σ EII,j (E)
, (2.446)
Σ Moller (E)
Σ EII,j (E) = p j σ EII,j (E) ρ N 0
W , (2.447)
where
R(E, J) = the cumulative distribution function of the ratio of the K-shell EII cross section of the
J-th element in a material to the Møller scattering cross section at electron energy E,
Σ Moller (E) = macroscopic Møller scattering cross section at electron energy E,
Σ EII,j (E) = macroscopic EII cross section of the j-th element at electron energy E,
σ EII,j (E) = microscopic EII cross section of the j-th element at electron energy E,
p j = proportion by number of the j-th element in the material,
ρ = density of a material,
N 0 = Avogadro’s number,
138