X-Rays

Front 1

List the ways X-rays can interact with matter. What do we call these?

Back 1

1) Photoelectric effect

2) Compton effect

3) Pair production

Called: Mechanisms of absorption

Front 2

Photoelectric effect

Back 2

1) Incident photon gives up all energy to eject an electron

2) Easy to distinguish between bone and soft tissue

3) Electron falls down energy levels, emitting a lower energy photon

Front 3

Compton effect

Back 3

1) Incident photon is scattered by an orbital electron

2) Some energy is given to the electron, travelling in a different direction to the deflected x-ray

Front 4

Pair production

Back 4

One photon turns into an electron and a positron near the nucleus of an atom

Front 5

List the absorption mechanisms in order of x-ray energy required (low to high)

Back 5

Photoelectric, Compton, pair production

Front 6

How does an x-ray tube produce x-rays?

Back 6

Electrons are accelerated from a cathode and lose energy in the form of x-rays (kinetic energy) when they collide with a tungsten target

Front 7

Characteristic x-rays depend on...

Back 7

The material of the electron target

Front 8

Collimated

Back 8

A parallel beam of uniform intensity

Front 9

Name a contrast medium

Back 9

Barium meal

Front 10

Contrast media

Back 10

A substance with a high proton number, ingested by the patient in order to view soft tissue with x-rays

Front 11

What causes low exposure on x-rays

Back 11

Substances with a high proton number

Front 12

Image intensifier screen

Back 12

Absorbs x-rays that would otherwise pass through the x-ray film and emits visible photons which are absorbed by the film

Front 13

CAT scan

Back 13

Computer axial tomography, an emitter and detector rotate around the patient to build up multiple slice images

Front 14

Intensity

Back 14

Power per unit cross sectional area