Polonium is an alpha-emitter, and is used as an ionising radiation source when plated onto metal surfaces: Method of plating polonium 1944). Applications include spark plugs.
A solid mass of polonium is self-heated by virtue of its radioactivity and this makes it useful as a thermal heat source: High purity polonium recovery (1976). It can be mixed or alloyed with boron: Method of preparing polonium-boron sources (1959) to provide a source of neutrons.
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