X-Ray Interactions With Matter

Flashcards covering key vocabulary and definitions related to x-ray interactions with matter, including coherent scattering, Compton effect, photoelectric effect, pair production, and photodisintegration.

Coherent Scattering

An interaction that occurs between very low energy x-ray photons (below 10 keV) and matter, where the photon's energy and wavelength remain the same but travels in a different direction.

Compton Effect

X-ray interaction with loosely bound electrons of tissue atoms which is responsible for scatter radiation.

Compton or Recoil Electron

The electron dislodged during Compton scattering.

Photoelectric Absorption Interaction

When an incident x-ray photon interacts with an inner shell electron, ejecting the electron and being totally absorbed in the interaction.

Photoelectron

The electron ejected during photoelectric absorption.

Secondary Radiation

Energy released in the form of a characteristic photon when an electron transfers from an outer shell to a vacant inner shell during the photoelectric interaction.

Pair Production

Interaction where the energy of the x-ray photon is converted to matter in the form of two electrons (a negatron and a positron), requiring a very high energy photon (energy greater than 1.02 MeV).

Annihilation Reaction

A process in which matter is converted back to energy when a positron unites with a free electron.

Photodisintegration

Interaction between an extremely high energy photon (above 10 MeV) and the nucleus of an atom, where the nucleus absorbs the photon's energy and emits a nuclear fragment.