Beta decay. A neutron in a nucleus changes into a proton, an electron, an
antineutrino and some energy (released as one or more gamma photon(s)).
The proton stays behind in the nucleus, the other particles leave.
Sit a single atom of a suitable isotope in a levitation cell (laser beam
crossfire).
Wait.
The exact time it takes for the beta decay to be observed is random--the
odds are 50-50 each half-life.
Or so they say.
MMB
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