Ionising Radiation

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Types of Ionising Radiation

Alpha Radiation: Consisting of an alpha particle, or a helium 4 nucleus. Stopped by paper.

Beta Radiation: A neutron is converted into a proton and an electron, the electron is ejected and is known as a beta particle. Stopped by thin aluminium.

Gamma Radiation: Highest energy electromagnetic radiation, emitted with the excess energy of other nuclear reactions. Stopped by centimetres of lead. No effect on neutron/proton count.

Detection

A Geiger-Muller counter is used to measure intensity of radiation. The tube is filled with gas which will be ionised when ionising radiation enters, quickly generating a current, which is then outputted as an audible click.

Photographic film will become fogged when exposed to ionising radiation.

Application

Gamma radiation is used to sterilise hospital equipment by killing bacteria.

Focused beams of gamma rays are used to kill cancerous cells in tumours.

Gamma emitters are used as tracers, and detected to create an accurate image of the inner workings of organs inside the body. This can also be used non-medically in machinery.

Carbon-14 is present in all living things as it is chemically identical to Carbon-12 and we can determine the age of organic material by measuring the ratio of 14 to 12, which is predictable.