G3 to G4
Rayleigh scattering for optical photon

Attenuation Length

• Geant3
  non-existent
  

• Geant4
  Optional: RayleighAttenuationLengthGenerator
  (uses Einstein-Smoluchowski formula,
  needs isothermal compressibility and temperature as medium properties.)
  Alternative: material properties in Materials Properties Table
  (input by user)
  

Final state

• Geant3
  non-existent
  

• Geant4
  Classical Rayleigh scattering formula for the scattering angle.