A broad beam describes a radiation shielding situation in which the beam impinging on a barrier surface is laterally extensive including scattered radiation.

The attenuation of radiation is a decrease in intensity as a result of interactions by transmission through matter. X-ray beams attenuate due to photon absorption by the material or scattering. Both effects are energy dependent. The probability of absorption or scattering is a function of the photon energy. The photoelectric absorption is much more energy dependent than the Compton scatter effect.

See also Attenuation Correction, Linear Energy Transfer, Broad Beam and Ion Beam.

A stream of electromagnetic or particulate radiation that could be collimated and is generally unidirectional or divergent usually from a small source and restricted to a small-solid angle.

See also Ion Beam, Broad Beam, Useful Beam and Beam On Time.