Gamma-Ray Interactions with Matter

The Photoelectric effect-

is when the photon is completely absorbed by the atom and an inner shell electron is ejected. The space is immediately filled by an electron from higher shells, leading to the emission of X-rays.

Compton Scattering-

Basically, a photon hits an electron causing it to be ejected and the photon scattered in a different direction.The photon is considered to be practically absorbed by the atom during this process.

Pair Production-

n

A gamma ray interacts with the electric field of an atomic nucleus and creates an electron and its antiparticle, the positron. nDuring this process the photon will disappear. nThe process is more likely to happen near the nucleus. nThe positron interacts with an electron, producing two gamma-rays traveling in opposite directions.

Elastic or Coherent Scattering-

A low-energy photon briefly interacts with an electron then continues on its way without any energy loss or gain of the electron or photon. During the interaction the electron will just oscillate at the same frequency as the photon. Also known as the Thomson or Classical scattering and when it happens to the whole atom is called Rayleigh scattering.

Photonuclear Reactions-

A photon is absorbed by an atom causing photodisintegration or the release of a nucleon. The photon must have more energy than the binding energy of the atom.

Intro
Types of Ionizing Radiation
Interactions with Matter
Alpha-Particle and Beta-Particle Interactions with Matter
Biological Interactions
Bibliography

n

 

n

n
 
n