Physics Bucharest 2017

Attenuation coefficient m

• Each photon interaction process it’s represented by its own attenuation coefficient ( e,t,s,k,z ). The sum of coefficients gives m • Photoelectric absorption, Compton effect and Pair production are dominant in the energy range of interest (0.1 – 100 MeV)

Photonuclear interactions (z)

Photoelectric effect (t)

m  e + t + s + k + z

Pair production (k)

Elastic scattering (e)

Compton effect (s)