| A | B |
|---|
| k-line emission | photons emitted when an electron falls to the lowest energy level of the atom |
| bremsstrahlung | radiation emitted when eletrons slow down |
| 1 eV | energy given to a electron when accelerated by 1 volt |
| tungsten | metal used as a target |
| thermionic emission | how electrons are made initially |
| filter grid | used to minimise the effect of scattered photons |
| tube voltage, Vp | voltage between cathode and anode |
| 15 - 150 kV | typical voltages for diagnostic X-rays |
| 70-90 kV | typical voltage for dental X-rays |
| beam hardening | removal of lower energy X-rays |
| tube current | the number of electrons travelling between the cathode and anode |
| half-thickness | thickness of absorber needed to halve the intensity |
| external beam radiation therapy | X-rays that come from outside the body |
| internal radiation therapy | when an isotope is planted in the body |
