Ionising Radiation
Quantum and Nuclear

Radioactive sources: isotopes and availability

Teaching Guidance for 14-16 PRACTICAL PHYISCS

In the UK, education suppliers stock only these three isotopes in sealed sources:

cobalt-60pure gamma (provided the low energy betas are filtered out)
strontium-90pure beta
americium-241alpha and some gamma

They are shown with the radiations that they emit.

However, you may have other sources in your school or Local Authority and, as long as you follow your school safety policy and local rules, you can use these in schools. The ones that are useful for practical work are:

radium-226alpha, beta and gamma
plutonium-239pure alpha
caesium-137beta, then gamma (from its decay product, metastable Ba-137)

For safety information:

Managing radioactive materials in schools

Ionising Radiation
is used in analyses relating to Radioactive dating
can be analysed using the quantity Half-Life Decay Constant Activity
features in Medical Physics
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